Substrate processing method

ABSTRACT

A liquid hydrophobizing agent is supplied to a substrate and a surface of the substrate is hydrophobized. A solvent, lower in surface tension than water and capable of dissolving the hydrophobizing agent, is supplied to the substrate in a pre-drying rinsing step. Thereafter, the substrate is dried. The substrate to be processed is maintained in a state of not contacting water until it is dried after being hydrophobized.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a substrate processing method and a substrateprocessing apparatus for processing a substrate. Examples of substratesto be processed include semiconductor wafers, substrates for liquidcrystal displays, substrates for plasma displays, substrates for FEDs(Field Emission Displays), substrates for optical disks, substrates formagnetic disks, substrates for magneto-optical disks, substrates forphotomasks, ceramic substrates, and substrates for solar cells.

2. Description of Related Art

In a production process for a semiconductor device or a liquid crystaldisplay, a substrate, such as a semiconductor wafer or a glass substratefor a liquid crystal display, is processed, for example, one by one.Specifically, a chemical solution is supplied to the substrate and asurface of the substrate is processed by the chemical solution.Thereafter, pure water is supplied and the chemical solution adhering tothe substrate is rinsed off. After the chemical solution has been rinsedoff, IPA (isopropyl alcohol), which is lower in boiling point thanwater, is supplied to the substrate and the pure water adhering to thesubstrate is replaced by IPA. Thereafter, the substrate is rotated athigh speed to remove the IPA adhering to the substrate from thesubstrate and the substrate is thereby dried.

However, with such a substrate processing method, a pattern formed onthe surface of the substrate may collapse during drying of thesubstrate. U.S. Patent Application Publication No. 2010/0240219 A1 thusdiscloses a method in which drying is performed after hydrophobizing thesurface of the substrate to prevent pattern collapse. Specifically, ahydrophobizing agent is supplied to the substrate to hydrophobize thesurface of the substrate. Thereafter, IPA is supplied to the substrateand the hydrophobizing agent adhering to the substrate is replaced byIPA. After replacement of the hydrophobizing agent by IPA, pure water issupplied to the substrate and the IPA adhering to the substrate isreplaced by pure water. Thereafter, the substrate is rotated at highspeed to dry the substrate.

SUMMARY OF THE INVENTION

Pattern collapse can be prevented if the surface of the substrate issufficiently hydrophobized. However, pattern collapse cannot beprevented if the surface of the substrate is not sufficientlyhydrophobized. That is, in a case where the surface of the substrate isonly partially hydrophobized or in a case where a contact angle of aprocessing liquid with respect to the substrate is not sufficientlylarge, pattern collapse cannot be prevented even if the substrate isdried after being hydrophobized.

When, as in the substrate processing method described in U.S. PatentApplication Publication No. 2010/0240219 A1, a single type ofhydrophobizing agent is supplied to the substrate, the surface of thesubstrate may not be hydrophobized sufficiently. Also, when a surfacetension of the processing liquid adhering to the substrate is high, alarge force is applied to the pattern during drying of the substrate.With the substrate processing method described in U.S. PatentApplication Publication No. 2010/0240219 A1, the substrate with purewater adhering thereto is dried. However, the surface tension of purewater is high and thus even if the substrate is hydrophobized, patterncollapse cannot be prevented sufficiently.

Meanwhile, even when a silylating agent is supplied as a hydrophobizingagent to a substrate having a metal film formed thereon, the metal filmis not hydrophobized and thus the substrate cannot be hydrophobizedsufficiently. However, if a metal hydrophobizing agent thathydrophobizes the metal is supplied to the substrate, the metal film canbe hydrophobized even in the case where the metal film is formed on thesubstrate. However, research by the present inventor has shown that evenwhen a metal hydrophobizing agent is used, there are cases where thesubstrate cannot be hydrophobized sufficiently.

Specifically, a metal hydrophobizing agent is not stable by itself andanother solvent (diluting solvent) must be mixed with the metalhydrophobizing agent. However, when a solvent containing a hydroxylgroup is mixed with the metal hydrophobizing agent, an ability (abilityto hydrophobize the substrate) of the metal hydrophobizing agent islowered. That is, in a case where a solvent containing a hydroxyl groupis mixed with the metal hydrophobizing agent or in a case where themetal hydrophobizing agent is supplied to a substrate holding a solventcontaining a hydroxyl group, the metal hydrophobizing agent cannotexhibits its ability sufficiently.

Further, even when a substrate is hydrophobized by a metalhydrophobizing agent, if after the metal hydrophobizing agent issupplied, a liquid or a vapor that contains water is supplied to thesubstrate, the contact angle of the processing liquid with respect tothe substrate decreases. The force applied to the pattern (the forcethat collapses the pattern) thus increases when the substrate is dried.Further, if the metal hydrophobizing agent is supplied to the surface ofthe substrate with water being held on the surface of the substrate, thesubstrate is not hydrophobized sufficiently. That is, the presentinventor found that even when a metal hydrophobizing agent is suppliedto a substrate on which a metal film is formed, the metal film cannot behydrophobized sufficiently under the presence of water.

Thus, an object of the present invention is to provide a substrateprocessing method and a substrate processing apparatus by which patterncollapse can be suppressed or prevented.

One embodiment of the present invention provides a substrate processingmethod including a hydrophobizing step of supplying a hydrophobizingagent to a substrate to hydrophobize a surface of the substrate, adrying step of drying the substrate after performing the hydrophobizingstep, and a step of maintaining the substrate in a state of notcontacting water from the end of the hydrophobizing step to the end ofthe drying step.

The surface of the substrate is a surface of the substrate itself and,in a case where a pattern is formed on the surface of the substrate,includes a surface of the pattern.

By this method, the hydrophobizing agent is supplied to the substrateand the surface of the substrate is thereby hydrophobized. Thereafter,the substrate is dried. The substrate to be processed is maintained inthe state of not contacting water until it is dried after beinghydrophobized. Significant decrease in hydrophobicity of the substratedue to contact with water after the hydrophobizing agent is supplied tothe substrate can thus be prevented. Pattern collapse can thereby besuppressed or prevented.

The substrate to be processed may be a substrate that includes a metalfilm or may be a substrate that does not include a metal film.

In a case where the substrate to be processed is a substrate thatincludes a metal film, the hydrophobizing agent is supplied to thesubstrate including the metal film and the metal film of the substrateis hydrophobized. Thereafter, the substrate is dried. The substrate tobe processed is maintained in the state of not contacting water until itis dried after being hydrophobized. If water contacts the substrate thathas been hydrophobized by the hydrophobizing agent that hydrophobizesthe metal film, the hydrophobicity of the substrate may decreasesignificantly. Thus, even when such a hydrophobizing agent is suppliedto the substrate, significant decrease in the hydrophobicity of thesubstrate can be prevented. Pattern collapse can thereby be suppressedor prevented.

Also, the hydrophobizing step may include a step of supplying a liquidof the hydrophobizing agent to the substrate, and the substrateprocessing method may further include a pre-drying rinsing step ofsupplying a solvent, lower in surface tension than water and capable ofdissolving the hydrophobizing agent, to the substrate after performingthe hydrophobizing step and before performing the drying step.

In this case, the solvent capable of dissolving the hydrophobizing agentis supplied to the substrate after the liquid of the hydrophobizingagent has been supplied to the substrate. The hydrophobizing agentadhering to the substrate is thus replaced by the solvent. The solventis then removed from the substrate and the substrate is dried. Thesolvent supplied to the substrate in the pre-drying rinsing step islower in surface tension than water. Pattern collapse can thus besuppressed or prevented more than in a case where a liquid that containswater is supplied to the substrate in the pre-drying rinsing step.

Also, the hydrophobizing step may include a vapor supply step ofsupplying a vapor of the hydrophobizing agent to the substrate, and thedrying step may include a vaporizing step of vaporizing thehydrophobizing agent adhering to the substrate.

In this case, the vapor of the hydrophobizing agent is supplied to thesubstrate. A portion of the vapor of the hydrophobizing agent suppliedto the substrate changes to liquid droplets and adheres to thesubstrate. However, the liquid droplets of the hydrophobizing agentvaporize and are removed from the substrate in a short time. Thesubstrate can thus be dried by vaporizing the hydrophobizing agentadhering to the substrate after performing the hydrophobizing step. Thesubstrate can thereby be dried rapidly to shorten the substrateprocessing time.

Another embodiment of the present invention provides a substrateprocessing apparatus including a substrate holding unit that holds asubstrate, a hydrophobizing agent supply unit that supplies ahydrophobizing agent to the substrate held by the substrate holdingunit, a drying unit that dries the substrate, and a controller thatperforms a hydrophobizing step of controlling the hydrophobizing agentsupply unit to supply the hydrophobizing agent to the substrate held bythe substrate holding unit to thereby hydrophobize a surface of thesubstrate, a drying step of controlling the drying unit to dry thesubstrate after performing the hydrophobizing step, and a step ofmaintaining the substrate in a state of not contacting water from theend of the hydrophobizing step to the end of the drying step. By thisarrangement, the same effects as the effects described above can beexhibited.

The substrate processing apparatus may further include a solvent supplyunit that supplies a solvent, lower in surface tension than water andcapable of dissolving the hydrophobizing agent, to the substrate held bythe substrate holding unit, and the hydrophobizing agent supply unit mayinclude a unit that supplies a liquid of the hydrophobizing agent to thesubstrate held by the substrate holding unit. The controller may performthe hydrophobizing step that includes a step of controlling thehydrophobizing agent supply unit to supply the liquid of thehydrophobizing agent to the substrate held by the substrate holding unitand perform a pre-drying rinsing step of controlling the solvent supplyunit to supply the solvent to the substrate held by the substrateholding unit after performing the hydrophobizing step and beforeperforming the drying step. In this case, the same effects as theeffects described above can be exhibited.

The hydrophobizing agent supply unit may further include a unit thatsupplies a vapor of the hydrophobizing agent to the substrate held bythe substrate holding unit. The controller may perform thehydrophobizing step that includes a vapor supply step of controlling thehydrophobizing agent supply unit to supply the vapor of thehydrophobizing agent to the substrate held by the substrate holding unitand performs the drying step that includes a vaporizing step ofcontrolling the drying unit to vaporize the hydrophobizing agentadhering to the substrate held by the substrate holding unit. In thiscase, the same effects as the effects described above can be exhibited.

Yet another embodiment of the present invention provides a substrateprocessing method for processing a substrate having a metal film formedthereon, the substrate processing method including a rinsing liquidsupply step of supplying a rinsing liquid that contains water to thesubstrate, a first solvent supply step of supplying a first solvent thatdoes not contain a hydroxyl group to the substrate to replace a liquidheld by the substrate by the first solvent after performing the rinsingliquid supply step, and a hydrophobizing agent supply step of supplyinga hydrophobizing agent, which contains a second solvent that does notcontain a hydroxyl group and which hydrophobizes a metal, to thesubstrate to replace a liquid held by the substrate by thehydrophobizing agent after performing the first solvent supply step.

The hydrophobizing agent supplied to the substrate may be a liquid ofthe hydrophobizing agent or may be a vapor of the hydrophobizing agent.Likewise, the first solvent supplied to the substrate may be a liquid ofthe first solvent or may be a vapor of the first solvent. The vapor ofthe hydrophobizing agent may be that obtained by gasification of thehydrophobizing agent or may be a mixed fluid containing liquid dropletsof the hydrophobizing agent and a carrier gas (for example, nitrogen gasor other inert gas) that carries the liquid droplets. The same appliesto the vapor of the first solvent.

By this method, the rinsing liquid that contains water is supplied tothe substrate having the metal film formed thereon. Thereafter, thefirst solvent that does not contain a hydroxyl group is supplied to thesubstrate, and the liquid (rinsing liquid or liquid containing therinsing liquid) held by the substrate is replaced by the first solvent.The rinsing liquid is thereby removed from the substrate. Then, afterthe first solvent has been supplied, the hydrophobizing agent, whichcontains the second solvent that does not contain a hydroxyl group andwhich hydrophobizes the metal, is supplied to the substrate. The liquid(liquid of the first solvent) held by the substrate is thereby replacedby the hydrophobizing agent. The liquid held by the substrate when thehydrophobizing agent is supplied to the substrate is the liquid of thefirst solvent. The first solvent does not contain a hydroxyl group andthus the lowering of the ability (ability to hydrophobize the substrate)of the hydrophobizing agent due to mixing of the hydrophobizing agentand the first solvent can be suppressed or prevented. Further, thehydrophobizing agent contains the second solvent that does not contain ahydroxyl group, and the hydrophobizing agent can thereby be stabilizedand the lowering of the ability of the hydrophobizing agent can besuppressed or prevented. Moreover, the rinsing liquid is removed fromthe substrate by the supply of the first solvent before thehydrophobizing agent is supplied to the substrate and thus thehydrophobizing agent is supplied to the substrate in a state where waterdoes not remain on the substrate or a state where a residual amount ofwater is extremely low. The substrate can thus be hydrophobizedsufficiently. Pattern collapse during drying of the substrate can thusbe suppressed or prevented.

The substrate processing method may further include a water-solublesolvent supply step of supplying a water-soluble solvent, higher insolubility in water than the first solvent, to the substrate to replacea liquid held by the substrate by the water-soluble solvent afterperforming the rinsing liquid supply step and before performing thefirst solvent supply step. The first solvent may be a solvent thatdissolves in water or may be a solvent that does not dissolve in water.

In this case, after the rinsing liquid that contains water has beensupplied to the substrate, the water-soluble solvent and the firstsolvent are successively supplied to the substrate in that order. Bysupplying the water-soluble solvent to the substrate holding the rinsingliquid, a large portion of the rinsing liquid held by the substrate isrinsed off and removed by the water-soluble solvent. Further, thewater-soluble solvent is higher in solubility in water than the firstsolvent, and thus in the process in which the rinsing liquid is replacedby the water-soluble solvent, a portion of the rinsing liquid held bythe substrate dissolves into the water-soluble solvent and is removedfrom the substrate together with the water-soluble solvent. By thensupplying the first solvent to the substrate after supplying thewater-soluble solvent, the water-soluble solvent held by the substrateis replaced by the first solvent. Even in a case where the rinsingliquid is contained in the water-soluble solvent held by the substrate,the rinsing liquid is removed from the substrate together with thewater-soluble solvent in the process of replacement of the water-solublesolvent by the first solvent. The residual amount of water on thesubstrate can thereby be reduced. The hydrophobizing agent can thus besupplied to the substrate in a state in which water is not left on thesubstrate or in a state in which the residual amount of water isextremely low. The substrate can thereby be hydrophobized sufficiently.Pattern collapse can thus be suppressed or prevented.

Also, the first solvent supply step may include a physical replacementstep of supplying the substrate with the first solvent with a physicalforce to replace a liquid held by the substrate by the first solvent.

In this case, the first solvent with the physical force applied theretois supplied to the substrate. The liquid (rinsing liquid or liquidcontaining the rinsing liquid) held by the substrate is removed from thesubstrate by the physical force applied to the first solvent in additionto a force of the first solvent flowing along the substrate. Theresidual amount of water on the substrate can thereby be reduced. Thehydrophobizing agent can thus be supplied to the substrate in a state inwhich water is not left on the substrate or in a state in which theresidual amount of water is extremely low. The substrate can thereby behydrophobized sufficiently. Pattern collapse can thus be suppressed orprevented.

Also, the first solvent supply step may further include a replacementstep of supplying the first solvent to the substrate to replace a liquidheld by the substrate by the first solvent before the physicalreplacement step is performed.

In this case, the first solvent is supplied to the substrate after therinsing liquid has been supplied to the substrate. Thereafter, the firstsolvent with the physical force applied thereto is supplied. That is,after the liquid (rinsing liquid or liquid containing the rinsingliquid) held by the substrate has been removed by the first supply ofthe first solvent, the first solvent with the physical force appliedthereto is supplied to the substrate. Thus, even when an extremely smallamount of the rinsing liquid remains on the substrate after the firstsupply of the first solvent, the slightly remaining rinsing liquid canbe removed from the substrate by the supply of the first solvent withthe physical force applied thereto. The hydrophobizing agent can thus besupplied to the substrate in a state in which water is not left on thesubstrate or in a state in which the residual amount of water isextremely low. The substrate can thereby be hydrophobized sufficiently.Pattern collapse can thus be suppressed or prevented.

Also, the physical replacement step may include at least one of either astep of supplying the first solvent with vibration to the substrate or astep of making liquid droplets of the first solvent provided withkinetic energy collide with the substrate.

In this case, the liquid (rinsing liquid or liquid containing therinsing liquid) held by the substrate is removed from the substrate bythe vibration of the first solvent and/or the kinetic energy of thefirst solvent in addition to the force of the first solvent flowingalong the substrate. The residual amount of water on the substrate canthereby be reduced. The hydrophobizing agent can thus be supplied to thesubstrate in a state in which water is not left on the substrate or in astate in which the residual amount of water is extremely low. Thesubstrate can thereby be hydrophobized sufficiently. Pattern collapsecan thus be suppressed or prevented.

Also, the substrate processing method may further include a drying stepof removing a liquid from the substrate to dry the substrate afterperforming the hydrophobizing agent supply step and a non-contact statemaintaining step of maintaining a state in which the substrate is not incontact with water from the end of the hydrophobizing agent supply stepto the end of the drying step.

In this case, the liquid is removed from the substrate after thehydrophobizing agent has been supplied to the substrate. The substrateis thereby dried. The substrate is prevented from contacting water fromthe end of the supply of the hydrophobizing agent to the end of thedrying of the substrate. A liquid or vapor containing water is thus notsupplied to the substrate from the end of the supply of thehydrophobizing agent to the end of the drying of the substrate.Reduction of contact angle of the processing liquid with respect to thesubstrate due to contact with water of the substrate to which thehydrophobizing agent has been supplied can thus be suppressed orprevented. Increase in a force applied to the pattern during drying ofthe substrate can thereby be suppressed or prevented. Pattern collapsecan thus be suppressed or prevented.

Also, the non-contact state maintaining step may include a drying agentsupply step of supplying a drying agent that does not contain water andis lower in boiling point than water to the substrate to replace aliquid held by the substrate by the drying agent after performing thehydrophobizing agent supply step and before performing the drying step.

In this case, the drying agent is supplied to the substrate after thehydrophobizing agent has been supplied to the substrate. The liquid heldby the substrate is thereby replaced by the drying agent. Thereafter,the drying agent is removed from the substrate and the substrate isdried. The drying agent does not contain water and thus reduction of thecontact angle of the processing liquid with respect to the substrate dueto the drying agent contacting the substrate to which the hydrophobizingagent has been supplied can be suppressed or prevented. Collapsing ofthe pattern during drying of the substrate can thereby be suppressed orprevented. Further, the drying agent is lower in boiling point thanwater and time required for drying can thus be shortened.

Also, the hydrophobizing agent supply step may include a step of mixingthe second solvent and a stock solution of the hydrophobizing agent in aflow path of the hydrophobizing agent leading from a hydrophobizingagent tank, storing the stock solution of the hydrophobizing agent to besupplied to the substrate, to the substrate, and a step of supplying themixed second solvent and stock solution of the hydrophobizing agent tothe substrate. “Stock solution of the hydrophobizing agent” refers to aliquid before mixing with the second solvent. That is, the “stocksolution of the hydrophobizing agent” may be a liquid that is diluted inadvance by a diluent (for example, the second solvent) or may be amixture of a plurality of liquids.

In this case, the second solvent and the stock solution of thehydrophobizing agent are mixed immediately before being supplied to thesubstrate. The mixed solution (hydrophobizing agent) of the secondsolvent and the stock solution of the hydrophobizing agent that aremixed is supplied to the substrate. The second solvent and the stocksolution of the hydrophobizing agent are mixed immediately before beingsupplied to the substrate and thus even in a case where thehydrophobizing agent decreases in activity with the elapse of time dueto dilution of the hydrophobizing agent, the hydrophobizing agent thatis not decreased in activity or is hardly decreased in activity can besupplied to the substrate. The substrate can thereby be hydrophobizedsufficiently. Pattern collapse can thus be suppressed or prevented.

Also, the first solvent and the second solvent may be the same type ofsolvent.

In this case, the hydrophobizing agent that contains the second solventis supplied to the substrate holding the first solvent that is thesolvent of the same type as the second solvent. The first solvent andthe hydrophobizing agent thus mix together smoothly and the firstsolvent held by the substrate is smoothly replaced by the hydrophobizingagent. The time required for replacement from the first solvent to thehydrophobizing agent can thereby be shortened.

Also, a recess portion having a bottomed cylindrical shape may be formedon the substrate. The recess portion may, for example, be a cylinderthat forms an electrode of a capacitor provided in a DRAM (dynamicrandom access memory) or a via hole for connection between wiringlayers.

In this case, the rinsing liquid is supplied to the substrate with therecess portion formed thereon. The recess portion has the bottomedcylindrical shape and the rinsing liquid thus readily remains at abottom of the recess portion. Thus, by supplying the first solvent,etc., to the substrate before supplying the hydrophobizing agent to thesubstrate, the rinsing liquid remaining at the bottom of the recessportion can be removed and the hydrophobizing agent can thus be suppliedto the substrate in a state in which water is not left on the substrateor in a state in which the residual amount of water is extremely low.The substrate can thereby be hydrophobized sufficiently. Patterncollapse can thus be suppressed or prevented.

Yet another embodiment of the present invention provides a substrateprocessing apparatus including a substrate holding unit that holds asubstrate, a rinsing liquid supply unit that supplies a rinsing liquidthat contains water to the substrate held by the substrate holding unit,a first solvent supply unit that supplies a first solvent that does notcontain a hydroxyl group to the substrate held by the substrate holdingunit, a hydrophobizing agent supply unit that supplies a hydrophobizingagent, which contains a second solvent that does not contain a hydroxylgroup and which hydrophobizes a metal, to the substrate held by thesubstrate holding unit, and a controller that performs a rinsing liquidsupply step of controlling the rinsing liquid supply unit to supply therinsing liquid to the substrate held by the substrate holding unit, afirst solvent supply step of controlling the first solvent supply unitto supply the first solvent to the substrate held by the substrateholding unit to replace a liquid held by the substrate by the firstsolvent after performing the rinsing liquid supply step, and ahydrophobizing agent supply step of controlling the hydrophobizing agentsupply unit to supply the hydrophobizing agent to the substrate held bythe substrate holding unit to replace a liquid held by the substrate bythe hydrophobizing agent after performing the first solvent supply step.In this case, the same effects as the effects described above can beexhibited.

The substrate processing apparatus may further include a water-solublesolvent supply unit that supplies a water-soluble solvent, higher insolubility in water than the first solvent, to the substrate. Thecontroller may further perform a water-soluble solvent supply step ofcontrolling the water-soluble solvent supply unit to supply thewater-soluble solvent to the substrate held by the substrate holdingunit to replace a liquid held by the substrate by the water-solublesolvent after performing the rinsing liquid supply step and beforeperforming the first solvent supply step. In this case, the same effectsas the effects described above can be exhibited.

Also, the substrate processing apparatus may further include a physicalforce applying unit that applies a physical force to the first solventto be supplied from the first solvent supply unit to the substrate heldby the substrate holding unit. The controller may perform the firstsolvent supply step that includes a physical replacement step ofreplacing the liquid held by the substrate by the first solvent bysupplying the first solvent with the physical force applied thereto bythe physical force applying unit to the substrate held by the substrateholding unit. In this case, the same effects as the effects describedabove can be exhibited.

Also, the controller may perform the first solvent supply step thatfurther includes a replacement step of controlling the first solventsupply unit to supply the first solvent to the substrate held by thesubstrate holding unit to replace a liquid held by the substrate by thefirst solvent before the physical replacement step is performed. In thiscase, the same effects as the effects described above can be exhibited.

Also, the physical force applying unit may include at least one ofeither a vibration applying unit that applies vibration to the firstsolvent to be supplied from the first solvent supply unit to thesubstrate held by the substrate holding unit or a liquid droplet formingunit that applies kinetic energy to the first solvent to be suppliedfrom the first solvent supply unit to the substrate held by thesubstrate holding unit to form liquid droplets of the first solvent. Inthis case, the same effects as the effects described above can beexhibited.

Also, the substrate processing apparatus may further include a dryingunit that removes a liquid from the substrate held by the substrateholding unit to dry the substrate and a non-contact state maintainingunit that maintains a state in which the substrate held by the substrateholding unit is not in contact with water. The controller may furtherperform a drying step of controlling the drying unit to remove theliquid from the substrate held by the substrate holding unit to dry thesubstrate after performing the hydrophobizing agent supply step and anon-contact state maintaining step of controlling the non-contact statemaintaining unit to maintain the state in which the substrate is not incontact with water from the end of the hydrophobizing agent supply stepto the end of the drying step. In this case, the same effects as theeffects described above can be exhibited.

Also, the non-contact state maintaining unit may include a drying agentsupply unit that supplies a drying agent that does not contain water andis lower in boiling point than water to the substrate. The controllermay perform the non-contact state maintaining step that includes adrying agent supply step of controlling the drying agent supply unit tosupply the drying agent to the substrate held by the substrate holdingunit to replace a liquid held by the substrate by the drying agent afterperforming the hydrophobizing agent supply step and before performingthe drying step. In this case, the same effects as the effects describedabove can be exhibited.

Also, the hydrophobizing agent supply unit may include a hydrophobizingagent tank that stores a stock solution of the hydrophobizing agent tobe supplied to the substrate held by the substrate holding unit, and asecond solvent tank that stores a second solvent to be supplied to aflow path of the hydrophobizing agent leading from the hydrophobizingagent tank to the substrate held by the substrate holding unit. In thiscase, the hydrophobizing agent supply unit may be arranged to mix thestock solution of the hydrophobizing agent and the second solvent storedin the flow path to supply the mixed second solvent and stock solutionof the hydrophobizing agent to the substrate held by the substrateholding unit. In this case, the same effects as the effects describedabove can be exhibited.

Yet another embodiment of the present invention provides a substrateprocessing method including a first hydrophobizing step of supplying afirst hydrophobizing agent to a substrate to hydrophobize a surface ofthe substrate, a second hydrophobizing step of supplying a secondhydrophobizing agent that differs from the first hydrophobizing agent tothe substrate to hydrophobize the surface of the substrate afterperforming the first hydrophobizing step, and a drying step of dryingthe substrate after performing the second hydrophobizing step. Thesurface of the substrate is a surface of the substrate itself and, in acase where a pattern is formed on the surface of the substrate, includesa surface of the pattern.

By this method, the first hydrophobizing agent is supplied to thesubstrate and the substrate is thereby hydrophobized. After the firsthydrophobizing agent has been supplied to the substrate, the secondhydrophobizing agent that differs from the first hydrophobizing agent issupplied to the substrate and the substrate is thereby furtherhydrophobized. Thereafter, the substrate is dried. The firsthydrophobizing agent and the second hydrophobizing agent may be suppliedto the substrate in liquid states or may be supplied to the substrate invapor states.

A plurality of types of hydrophobizing agents are thus supplied to thesubstrate and thus even in a case of processing a substrate on which apattern of a laminated film that includes a plurality of films ofdifferent types is formed, the entire surface of the substrate can behydrophobized sufficiently. Further, even in a case where hydrophobicityis not increased sufficiently by one type of hydrophobizing agent, thesurface of the substrate can be hydrophobized sufficiently. Patterncollapse can thereby be suppressed or prevented.

The substrate processing method may include a step of maintaining thesurface of the substrate in a state of not contacting water from the endof the first hydrophobizing step or the second hydrophobizing step tothe end of the drying step.

In this case, the hydrophobized surface of the substrate is maintainedin the state of not contacting water until the substrate is dried. Whenwater contacts the substrate that has been hydrophobized by ahydrophobizing agent that hydrophobizes a metal film, the hydrophobicityof the substrate may decrease significantly. Thus, even when such ahydrophobizing agent is supplied to the substrate, significant decreasein the hydrophobicity of the substrate can be prevented. Patterncollapse can thereby be suppressed or prevented.

Also, the substrate processing method may be a method for processing asubstrate on which a pattern of a laminated film having a lower layerfilm and an upper layer film is formed, the first hydrophobizing agentmay be a hydrophobizing agent that hydrophobizes the lower layer film,and the second hydrophobizing agent may be a hydrophobizing agent thathydrophobizes the upper layer film.

In this case, after the lower layer film has been hydrophobized by thefirst hydrophobizing agent or after the lower layer film and the upperlayer film have been hydrophobized by the first hydrophobizing agent,the upper layer film is hydrophobized by the second hydrophobizingagent. For example, when a hydrophobizing agent is further supplied tothe substrate after the upper layer film has been hydrophobized, thehydrophobizing agent may not be supplied sufficiently to the lower layerfilm because the upper layer film is hydrophobized. Thus, by supplyingthe second hydrophobizing agent that hydrophobizes the upper layer filmto the substrate after the lower layer film has been hydrophobized orthe lower layer film and the upper layer film have been hydrophobized,the upper layer film and the lower layer film can be hydrophobizedsufficiently. The substrate can thereby be hydrophobized sufficiently.

Also, the substrate processing method may further include a waterrinsing step of supplying a rinsing liquid that contains water to thesubstrate before the first hydrophobizing step is performed, and a firstsolvent rinsing step of supplying a first solvent capable of dissolvingthe rinsing liquid and the first hydrophobizing agent to the substrateafter performing the water rinsing step and before performing the firsthydrophobizing step.

In this case, the rinsing liquid that contains water is supplied to thesubstrate. Thereafter, the first solvent capable of dissolving therinsing liquid and the first hydrophobizing agent is supplied to thesubstrate. The rinsing liquid adhering to the substrate is therebyreplaced by the first solvent. The first hydrophobizing agent and thesecond hydrophobizing agent are thus supplied to the substrate in astate where the rinsing liquid has been removed. The firsthydrophobizing agent and the second hydrophobizing agent are thusprevented from contacting the water contained in the rinsing liquid.Thus, in a case where hydrophobizing agents that decrease in activityupon contact with water are used as the first hydrophobizing agent andthe second hydrophobizing agent, decreases in the activities of thefirst hydrophobizing agent and the second hydrophobizing agent areprevented. The substrate can thereby be hydrophobized sufficiently.

Also, a second solvent rinsing step of supplying a second solventcapable of dissolving the first hydrophobizing agent and the secondhydrophobizing agent to the substrate after performing the firsthydrophobizing step and before performing the second hydrophobizing stepmay further be included.

In this case, the second solvent capable of dissolving the firsthydrophobizing agent and the second hydrophobizing agent is supplied tothe substrate after performing the first hydrophobizing step and beforeperforming the second hydrophobizing step. For example, when, in a casewhere the first hydrophobizing agent and the second hydrophobizing agentdo not readily mix together, the second hydrophobizing agent is suppliedto the substrate in a state where the first hydrophobizing agent isadhering to the substrate, the first hydrophobizing agent adhering tothe substrate cannot be replaced readily by the second hydrophobizingagent. The second hydrophobizing agent thus does not contact the surfaceof the substrate sufficiently.

Meanwhile, the second solvent can dissolve the first hydrophobizingagent and the second hydrophobizing agent. Thus, by supplying the secondsolvent to the substrate after performing the first hydrophobizing step,the first hydrophobizing agent adhering to the substrate can be replacedby the second solvent and the first hydrophobizing agent can thereby beremoved from the substrate. Then, by supplying the second hydrophobizingagent to the substrate after performing the second solvent rinsing step,the second solvent adhering to the substrate can be replaced by thesecond hydrophobizing agent and the second solvent can thus be removedfrom the substrate. Thus, even in the case where the firsthydrophobizing agent and the second hydrophobizing agent do not readilymix together, the first hydrophobizing agent adhering to the substratecan be replaced by the second hydrophobizing agent. The secondhydrophobizing agent can thereby be made to react with the substrate andthe substrate can be hydrophobized by the second hydrophobizing agent.

Also, the first hydrophobizing step may include a first vapor supplystep of supplying a vapor of the first hydrophobizing agent to thesubstrate, and the second hydrophobizing step may include a second vaporsupply step of supplying a vapor of the second hydrophobizing agent tothe substrate. The drying step may include a vaporizing step ofvaporizing the second hydrophobizing agent adhering to the substrate.

In this case, after the vapor of the first hydrophobizing agent has beensupplied to the substrate, the vapor of the second hydrophobizing agentis supplied to the substrate. Portions of the vapors of the firsthydrophobizing agent and the second hydrophobizing agent supplied to thesubstrate change to liquid droplets and adhere to the substrate.However, the liquid droplets of the first hydrophobizing agent and thesecond hydrophobizing agent vaporize and are thereby removed from thesubstrate in a short time. The substrate can thus be dried by vaporizingthe second hydrophobizing agent adhering to the substrate afterperforming the second hydrophobizing step. The substrate can thereby bedried rapidly and the substrate processing time can be shortened.

Yet another embodiment of the present invention provides a substrateprocessing apparatus including a substrate holding unit that holds asubstrate, a first hydrophobizing agent supply unit that supplies afirst hydrophobizing agent to the substrate held by the substrateholding unit, a second hydrophobizing agent supply unit that supplies asecond hydrophobizing agent differing from the first hydrophobizingagent to the substrate held by the substrate holding unit, drying unitthat dries the substrate, and a controller that controls the firsthydrophobizing agent supply unit, the second hydrophobizing agent supplyunit, and the drying unit to supply the first hydrophobizing agent tothe substrate to hydrophobize the surface of the substrate, thereaftersupply the second hydrophobizing agent to the substrate to hydrophobizethe surface of the substrate, and thereafter dry the substrate. By thisarrangement, the same effects as the effects described above can beexhibited.

The foregoing and other objects, features and effects of the presentinvention will become more apparent from the following detaileddescription of the preferred embodiments with reference to the attacheddrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a general arrangement of a substrateprocessing apparatus according to a first embodiment of the presentinvention.

FIG. 2 is a schematic view of the general arrangement of the substrateprocessing apparatus according to the first embodiment of the presentinvention.

FIG. 3 is a block diagram for describing an electrical arrangement ofthe substrate processing apparatus according to the first embodiment ofthe present invention.

FIG. 4 is a schematic view of a general arrangement of a firsthydrophobizing agent supply unit according to the first embodiment ofthe present invention.

FIG. 5 is a process chart for describing a first processing example ofprocessing a substrate by the substrate processing apparatus accordingto the first embodiment of the present invention.

FIG. 6 is a process chart for describing a second processing example ofprocessing a substrate by the substrate processing apparatus accordingto the first embodiment of the present invention.

FIG. 7 is a sectional view of an example of a substrate processed by thesubstrate processing apparatus according to the first embodiment of thepresent invention.

FIG. 8 is a table for describing hydrophobizing agents used in a casewhere a first film, a second film, and a third film are asilicon-containing film, a silicon-containing film, and a metal film,respectively.

FIG. 9 is a table for describing hydrophobizing agents used in a casewhere a first film, a second film, and a third film are an SiN film, aBSG film, and a polysilicon film, respectively.

FIG. 10 is a table for describing hydrophobizing agents used in a casewhere a first film, a second film, and a third film are an SiN film, ametal film, and an arbitrary film, respectively.

FIG. 11 is a graph of contact angles of pure water with respect to SiO₂and TiN test pieces that were immersed in a silicon hydrophobizingagent.

FIG. 12 is a graph of contact angles of pure water with respect to SiO₂and TiN test pieces that were immersed in a metal hydrophobizing agent.

FIG. 13 is a graph of contact angles of pure water with respect to SiO₂,TiN, and W test pieces that were successively immersed in the siliconhydrophobizing agent and the metal hydrophobizing agent.

FIG. 14 is a graph of contact angles before and after rinsing processingof a metal-containing compound that was immersed in a metalhydrophobizing agent.

FIG. 15 is a schematic diagram of changes in a surface state of SiN whena silicon hydrophobizing agent I and a silicon hydrophobizing agent IIare successively supplied to SiN.

FIG. 16 is a schematic sectional view of a substrate for describing aforce applied to patterns.

FIG. 17 is a schematic view of a general arrangement of a substrateprocessing apparatus according to a second embodiment of the presentinvention.

FIG. 18 is a schematic view of a general arrangement of a firsthydrophobizing agent supply unit according to the second embodiment ofthe present invention.

FIG. 19 is a process chart for describing a third processing example ofprocessing a substrate by the substrate processing apparatus accordingto the second embodiment of the present invention.

FIG. 20 is a process chart for describing a fourth processing example ofprocessing a substrate by the substrate processing apparatus accordingto the second embodiment of the present invention.

FIG. 21 is a schematic view of a general arrangement of a substrateprocessing apparatus according to a third embodiment of the presentinvention.

FIG. 22 is a schematic view of the general arrangement of the substrateprocessing apparatus according to the third embodiment of the presentinvention.

FIG. 23 is a block diagram for describing an electrical arrangement ofthe substrate processing apparatus according to the third embodiment ofthe present invention.

FIG. 24 is a schematic view of a general arrangement of a hydrophobizingagent supply unit according to the third embodiment of the presentinvention.

FIG. 25 is a process chart for describing a processing example ofprocessing a substrate by the substrate processing apparatus accordingto the third embodiment of the present invention.

FIG. 26 is a schematic sectional view of a substrate for describing aforce applied to patterns.

FIG. 27 is a graph of contact angles of a processing liquid with respectto a substrate, hydrophobized by a hydrophobizing agent, before andafter pure water is supplied to the substrate.

FIG. 28 is a graph of pattern collapse rates when a substrate,hydrophobized by a hydrophobizing agent, is dried after supplying purewater or IPA to the substrate.

FIG. 29 is a graph of the pattern collapse rate of a substrate processedby a conventional processing method and the pattern collapse rate of asubstrate processed by the processing example of FIG. 25.

FIG. 30 is a schematic view of a liquid droplet forming nozzle accordingto a fourth embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[First Embodiment]

Each of FIG. 1 and FIG. 2 is a schematic view of a general arrangementof a substrate processing apparatus 1 according to a first embodiment ofthe present invention. FIG. 3 is a block diagram for describing anelectrical arrangement of the substrate processing apparatus 1 accordingto the first embodiment of the present invention.

The substrate processing apparatus 1 is a single substrate processingtype substrate processing apparatus that processes a semiconductor waferor other substrate W one at a time by a chemical solution, a rinsingliquid, and other processing liquids. As shown in FIG. 1 and FIG. 2, thesubstrate processing apparatus 1 includes a spin chuck 2 (substrateholding unit, drying unit) that horizontally holds and rotates thesubstrate W, a shielding plate 3 disposed above the spin chuck 2, and aprocessing liquid supply mechanism 4 that supplies the processingliquids to the substrate W held by the spin chuck 2.

The spin chuck 2 is, for example, a gripping type substrate holding unitthat grips and holds the substrate W. The spin chuck 2 includes, forexample, a disk-shaped spin base 5 that is disposed horizontally, aplurality of gripping members 6 disposed on the spin base 5, and a spinmotor 7 coupled to the spin base 5. The spin chuck 2 can grip thesubstrate W from the periphery by putting the respective grippingmembers 6 in contact with a peripheral end surface of the substrate W.Further, the spin chuck 2 can rotate the substrate W about a verticalrotational axis passing through a center of the substrate W bytransmitting a driving force of the spin motor 7 to the spin base 5while holding the substrate W. The spin chuck 2 is not restricted to agripping type substrate holding unit and may be a substrate holding unitof another form, such as a vacuum type that suctions and holds a lowersurface (rear surface) of the substrate W.

Also, the shielding plate 3 has, for example, a disk shape. A diameterof the shielding plate 3 is, for example, substantially the same as adiameter of the substrate W or slightly greater than the diameter of thesubstrate W. The shielding plate 3 is disposed so that a lower surfaceof the shielding plate 3 is horizontal. Further, the shielding plate 3is disposed so that a central axis of the shielding plate 3 ispositioned along the rotational axis of the spin chuck 2. The lowersurface of the shielding plate 3 faces an upper surface of the substrateW held by the spin chuck 2. The shielding plate 3 is coupled in thehorizontal posture to a lower end of a support shaft 8. The shieldingplate 3 and the support shaft 8 are raised and lowered in a verticaldirection by a shielding plate elevating mechanism 9. The shieldingplate elevating mechanism 9 raises and lowers the shielding plate 3between a processing position (position shown in FIG. 2) at which thelower surface of the shielding plate 3 is set close to the upper surfaceof the substrate W held by the spin chuck 2 and a retreat position(position shown in FIG. 1) set above the processing position.

The processing liquid supply mechanism 4 includes a chemical solutionnozzle 10, a chemical solution supply pipe 11, and a chemical solutionvalve 12. The chemical solution supply pipe 11 is connected to thechemical solution nozzle 10. The chemical solution valve 12 isinterposed in the chemical solution supply pipe 11. When the chemicalsolution valve 12 is opened, a chemical solution is supplied from thechemical solution supply pipe 11 to the chemical solution nozzle 10.Also, when the chemical solution valve 12 is closed, the supply of thechemical solution from the chemical solution supply pipe 11 to thechemical solution nozzle 10 is stopped. The chemical solution nozzle 10is coupled to a nozzle moving mechanism 13. The nozzle moving mechanism13 moves the chemical solution nozzle 10 between a processing position(position shown in FIG. 1) set above the spin chuck 2 and a retreatposition (position shown in FIG. 2) set at a position away from theprocessing position. The processing position is set so that the chemicalsolution discharged from the chemical solution nozzle 10 is supplied toa central portion of the upper surface of the substrate W held by thespin chuck 2 (see FIG. 1).

Also, the processing liquid supply mechanism 4 includes a central axisnozzle 14 and a processing liquid supply pipe 15. The central axisnozzle 14 is disposed along the central axis of the shielding plate 3.The central axis nozzle 14 extends vertically in an interior of thesupport shaft 8. The central axis nozzle 14 is raised and lowered alongwith the shielding plate 3 and the support shaft 8. The processingliquid supply pipe 15 is connected to the central axis nozzle 14 abovethe shielding plate 3. For example, a hydrophobizing agent, a solvent, arinsing liquid, and other processing liquids are supplied from theprocessing liquid supply pipe 15 to the central axis nozzle 14. Theprocessing liquid supplied to the central axis nozzle 14 is dischargeddownward from a lower end of the central axis nozzle 14. The processingliquid discharged from the central axis nozzle 14 passes through athrough-hole (not shown) that passes vertically through a centralportion of the shielding plate 3 and is discharged downward from acentral portion of the lower surface of the shielding plate 3 (see FIG.2). The processing liquid is thereby supplied to the central portion ofthe upper surface of the substrate W held by the spin chuck 2.

The processing liquid supply mechanism 4 includes two hydrophobizingagent supply units 16 and 17, a solvent supply pipe 19 having a solventvalve 18 (solvent supply unit) interposed therein, and a rinsing liquidsupply pipe 21 having a rinsing liquid valve 20 interposed therein. Theprocessing liquid supply pipe 15 is connected to the respectivehydrophobizing agent supply units 16 and 17, the solvent supply pipe 19,and the rinsing liquid supply pipe 21. A first hydrophobizing agent(liquid) is supplied from the first hydrophobizing agent supply unit 16(hydrophobizing agent supply unit, first hydrophobizing agent supplyunit) to the processing liquid supply pipe 15. A second hydrophobizingagent (liquid) is supplied from the second hydrophobizing agent supplyunit 17 (hydrophobizing agent supply unit, second hydrophobizing agentsupply unit) to the processing liquid supply pipe 15. Also, when thesolvent valve 18 is opened, a solvent (liquid) is supplied from thesolvent supply pipe 19 to the processing liquid supply pipe 15.Likewise, when the rinsing liquid valve 20 is opened, a rinsing liquidis supplied from the rinsing liquid supply pipe 21 to the processingliquid supply pipe 15.

The rinsing liquid is a liquid that contains water. The rinsing liquidis, for example, any of pure water (deionized water), carbonated water,electrolyzed ion water, hydrogen water, ozone water, or aqueoushydrochloric acid of dilute concentration (for example, about 10 to 100ppm).

The first hydrophobizing agent and the second hydrophobizing agent aremutually different types of hydrophobizing agents. The firsthydrophobizing agent and the second hydrophobizing agent are liquidsthat do not contain water. The first hydrophobizing agent is, forexample, a silicon hydrophobizing agent that hydrophobizes siliconitself or a compound that contains silicon, or a metal hydrophobizingagent that hydrophobizes a metal itself or a compound that contains ametal. The same applies to the second hydrophobizing agent.

The metal hydrophobizing agent contains, for example, at least one of anamine having a hydrophobic group and an organosilicon compound.

The silicon hydrophobizing agent is, for example, a silane couplingagent. The silane coupling agent contains, for example, at least one ofHMDS (hexamethyldisilazane), TMS (tetramethylsilane), a fluorinatedalkylchlorosilane, an alkyldisilazane, and a nonchloro hydrophobizingagent.

The nonchloro hydrophobizing agent contains, for example, at least oneof dimethylsilyldimethylamine, dimethylsilyldiethylamine,hexamethyldisilazane, tetramethyldisilazane,bis(dimethylamino)dimethylsilane, N,N-dimethylaminotrimethylsilane,N-(trimethylsilyl)dimethylamine, and an organosilane compound.

The solvent is a liquid that is capable of dissolving the hydrophobizingagent and water but does not contain water. The solvent contains, forexample, at least one of an alcohol, a ketone, PGMEA (propylene glycolmonomethyl ether acetate), EGMEA (ethylene glycol monomethyl etheracetate), and a fluorine-based solvent. The solvent is lower in surfacetension than water and is lower in boiling point than water.

The alcohol contains, for example, at least one of methyl alcohol,ethanol, propyl alcohol, and IPA (isopropyl alcohol).

The ketone contains, for example, at least one of acetone and diethylketone.

The fluorine-based solvent contains, for example, at least one of an HFE(hydrofluoroether) and an HFC (hydrofluorocarbon).

As shown in FIG. 3, the substrate processing apparatus 1 includes acontroller 22. The spin motor 7, the shielding plate elevating mechanism13, and the respective hydrophobizing agent supply units 16 and 17 arecontrolled by the controller 22. Also, opening and closing of therespective valves included in the substrate processing apparatus 1 arecontrolled by the controller 22. As shown in FIG. 1, the controller 22positions the chemical solution nozzle 10 at the processing position andcauses the chemical solution to be discharged from the chemical solutionnozzle 10 while the substrate W is being rotated by the spin chuck 2.The chemical solution discharged from the chemical solution nozzle 10 issupplied to the central portion of the upper surface of the substrate Wheld by the spin chuck 2. The chemical solution supplied to the centralportion of the upper surface of the substrate W receives a centrifugalforce due to rotation of the substrate W and spreads outward along thesubstrate W. The chemical solution is thereby supplied to an entireupper surface of the substrate W and the substrate W is processed by thechemical solution.

On the other hand, as shown in FIG. 2, the controller 22 positions theshielding plate 3 at the processing position and causes a processingliquid to be discharged from the central axis nozzle 14 while thesubstrate W is being rotated by the spin chuck 2. The processing liquiddischarged from the central axis nozzle 14 is supplied to the centralportion of the upper surface of the substrate W held by the spin chuck2. The processing liquid supplied to the central portion of the uppersurface of the substrate W receives the centrifugal force due torotation of the substrate W and spreads outward along the substrate W.The processing liquid is thereby supplied to the entire upper surface ofthe substrate W and the substrate W is processed by the processingliquid. Also, the processing liquid that is shaken off to the peripheryof the substrate W is suppressed or prevented from splashing back andadhering to the substrate W because the processing liquid is supplied tothe substrate W with the lower surface of the shielding plate 3 beingset close to the upper surface of the substrate W.

FIG. 4 is a schematic view of a general arrangement of the firsthydrophobizing agent supply unit 16 according to the first embodiment ofthe present invention. In the following description, the generalarrangement of the first hydrophobizing agent supply unit 16 shall bedescribed. The general arrangement of the second hydrophobizing agentsupply unit 17 is the same as that of the first hydrophobizing agentsupply unit 16 and description thereof shall thus be omitted.

The hydrophobizing agent supply unit 16 includes a first tank 23 storingthe first hydrophobizing agent (liquid) and a second tank 24 storing adiluting solvent (liquid). Further, the first hydrophobizing agentsupply unit 16 includes a first pipe 25 connected to the first tank 23,a second pipe 26 connected to the second tank 24, a first valve 27 and afirst flow regulating valve 28 interposed in the first pipe 25, a secondvalve 29 and a second flow regulating valve 30 interposed in the secondpipe 26, and a collective pipe 31 connected to the first pipe 25 and thesecond pipe 26.

The first hydrophobizing agent stored in the first tank 23 is suppliedto the first pipe 25, for example, by being suctioned by a pump or by anair pressure inside the first tank 23 being raised by of a gas suppliedinto the first tank 23. The same applies to the diluting solvent. Thecollective pipe 31 is connected to the processing liquid supply pipe 15(see FIG. 1 and FIG. 2). Also, the opening and closing of the firstvalve 27 and the second valve 29 are controlled by the controller 22.Also, opening degrees of the first flow regulating valve 28 and thesecond flow regulating valve 30 are controlled by the controller 22.

When the controller 22 opens the first valve 27, the firsthydrophobizing agent stored in the first tank 23 is supplied to thecollective pipe 31 at a flow rate in accordance with the opening degreeof the first flow regulating valve 28. Likewise, when the controller 22opens the second valve 29, the diluting solvent stored in the secondtank 24 is supplied to the collective pipe 31 at a flow rate inaccordance with the opening degree of the second flow regulating valve30. The first hydrophobizing agent and the diluting solvent are therebymixed inside the collective pipe 31. The diluting solvent thus dissolvesin the first hydrophobizing agent and the first hydrophobizing agent isdiluted. The diluted first hydrophobizing agent is supplied from thecollective pipe 31 to the processing liquid supply pipe 15 and isdischarged from the central axis nozzle 14. The first hydrophobizingagent may be supplied in the diluted state to the central axis nozzle 14or may be supplied to the central axis nozzle 14 without being diluted.For example, in a case where the first hydrophobizing agent is anorganosilicon compound that is an example of a metal hydrophobizingagent, the first hydrophobizing agent is preferably supplied to thecentral axis nozzle 14 without being diluted.

The diluting solvent is a liquid that can dissolve the hydrophobizingagent, the solvent, and water and yet does not contain water. Thediluting solvent contains, for example, at least one of an alcohol(monohydric alcohol), a polyhydric alcohol, a ketone, PGMEA, EGMEA, anda fluorine-based solvent. The diluting solvent is lower in surfacetension than water and is lower in boiling point than water.

The alcohol contains, for example, at least one of methyl alcohol,ethanol, propyl alcohol, and IPA.

The polyhydric alcohol contains, for example, ethylene glycol.

The ketone contains, for example, at least one of acetone and diethylketone.

The fluorine-based solvent contains, for example, at least one of an HFEand an HFC (hydrofluorocarbon).

In a case where the first hydrophobizing agent is an amine having ahydrophobic group, which is an example of a metal hydrophobizing agent,a hydrophilic solvent is used as the diluting solvent. That is, amonohydric alcohol, such as methyl alcohol, ethanol, IPA, propylalcohol, etc., a polyhydric alcohol, such as ethylene glycol, etc., or aketone, such as acetone, diethyl ketone, etc., is used as the dilutingsolvent.

FIG. 5 is a process chart for describing a first processing example ofprocessing a substrate W by the substrate processing apparatus 1according to the first embodiment of the present invention. In thefollowing description, the processing example of processing thesubstrate W having patterns P (see FIG. 7) formed on a front surface,which is a device forming surface, shall be described with reference toFIG. 1, FIG. 2, and FIG. 5. Also, in the following description, “uppersurface (front surface) of the substrate W” includes the upper surface(front surface) of the substrate W itself and surfaces of the patternsP.

An unprocessed substrate W is transferred by an unillustrated transferrobot and is placed on the spin chuck 2, for example, with the frontsurface that is the device forming surface faced upward. The controller22 then controls the spin chuck 2 and makes it hold the placed substrateW. When the substrate W is being transferred onto the spin chuck 2, thecontroller 22 positions the chemical solution nozzle 10 and theshielding plate 3 at the respective retreat positions to prevent thetransfer robot and the substrate W from colliding with the chemicalsolution nozzle 10 and the shielding plate 3.

Thereafter, a chemical solution processing of supplying the chemicalsolution to the substrate W is performed (S101). Specifically, thecontroller 22 controls the nozzle moving mechanism 13 to move thechemical solution nozzle 10 from the retreat position to the processingposition with the shielding plate 3 being positioned at the retreatposition. Also, the controller 22 controls the spin motor 7 to rotatethe substrate W held by the spin chuck 2. The controller 22 then causesthe chemical solution to be discharged from the chemical solution nozzle10 toward the central portion of the upper surface of the substrate Wwhile making the substrate W rotate by the spin chuck 2. The chemicalsolution is thereby supplied to the entire upper surface of thesubstrate W and the substrate W is processed by the chemical solution(chemical solution processing). Then, when the chemical solutionprocessing has been performed for a predetermined time, the controller22 closes the chemical solution valve 12 to stop the discharge of thechemical solution. Thereafter, the controller 22 controls the nozzlemoving mechanism 13 to move the chemical solution nozzle 10 to theretreat position.

Thereafter, a water rinsing processing (water rinsing step) of supplyingpure water, which is an example of a rinsing liquid, to the substrate Wis performed (S102). Specifically, the controller 22 controls theshielding plate elevating mechanism 9 to move the shielding plate 3 fromthe retreat position to the processing position with the chemicalsolution nozzle 10 being positioned at the retreat position. Thecontroller 22 then opens the rinsing liquid valve 20 to cause pure waterto be discharged from the central axis nozzle 14 toward the centralportion of the upper surface of the substrate W while making thesubstrate W rotate by the spin chuck 2. Pure water is thereby suppliedto the entire upper surface of the substrate W and the chemical solutionadhering to the substrate W is rinsed off by the pure water (waterrinsing processing). Then, when the water rinsing processing has beenperformed for a predetermined time, the controller 22 closes the rinsingliquid valve 20 to stop the discharge of pure water.

Thereafter, a first solvent rinsing processing (first solvent rinsingstep) of supplying the solvent to the substrate W is performed (S103).Specifically, the controller 22 opens the solvent valve 18 to cause thesolvent to be discharged from the central axis nozzle 14 toward thecentral portion of the upper surface of the substrate W whilepositioning the shielding plate 3 at the processing position and furthermaking the substrate W rotate by the spin chuck 2. The solventdischarged from the central axis nozzle 14 is thereby supplied as thefirst solvent to the entire upper surface of the substrate W. Asmentioned above, the solvent is a liquid that can dissolve water andthus the pure water adhering to the substrate W dissolves into thesolvent supplied to the substrate W. Thus, by supplying the solvent tothe entire upper surface of the substrate W, the pure water adhering tothe substrate W is rinsed off by the solvent and is replaced by thesolvent (first solvent rinsing processing). Then, when the first solventrinsing processing has been performed for a predetermined time, thecontroller 22 closes the solvent valve 18 to stop the discharge of thesolvent.

Thereafter, a first hydrophobization processing (hydrophobizing step,first hydrophobizing step) of supplying the first hydrophobizing agent(liquid) to the substrate W is performed (S104). Specifically, thecontroller 22 controls the first hydrophobizing agent supply unit 16 tocause the first hydrophobizing agent to be discharged from the centralaxis nozzle 14 toward the central portion of the upper surface of thesubstrate W while positioning the shielding plate 3 at the processingposition and further making the substrate W rotate by the spin chuck 2.The first hydrophobizing agent is thereby supplied to the entire uppersurface of the substrate W. As mentioned above, the solvent is a liquidthat can dissolve the hydrophobizing agent and thus by supplying thefirst hydrophobizing agent to the entire upper surface of the substrateW, the solvent adhering to the substrate W is replaced by the firsthydrophobizing agent. The first hydrophobizing agent is thereby made toenter into internal portions of the patterns P and the upper surface ofthe substrate W is thereby hydrophobized (first hydrophobizationprocessing). Then, when the first hydrophobization processing has beenperformed for a predetermined time, the controller 22 controls the firsthydrophobizing agent supply unit 16 to stop the discharge of the firsthydrophobizing agent.

Thereafter, a pre-drying rinsing processing (pre-drying rinsing step) ofsupplying the solvent to the substrate W is performed (S105).Specifically, the controller 22 opens the solvent valve 18 to cause thesolvent to be discharged from the central axis nozzle 14 toward thecentral portion of the upper surface of the substrate W whilepositioning the shielding plate 3 at the processing position and furthermaking the substrate W rotate by the spin chuck 2. The solventdischarged from the central axis nozzle 14 is thereby supplied to theentire upper surface of the substrate W. The first hydrophobizing agentadhering to the substrate W is thus replaced by the solvent (pre-dryingrinsing processing). Then, when the pre-drying rinsing processing hasbeen performed for a predetermined time, the controller 22 closes thesolvent valve 18 to stop the discharge of the solvent.

Thereafter, a drying processing (drying step) of drying the substrate Wis performed (S106). Specifically, the controller 22 controls the spinmotor 7 to rotate the substrate W at a high rotation speed (for example,several thousand rpm) with the shielding plate 3 being positioned at theprocessing position. A large centrifugal force thus acts on the solventadhering to the substrate W and the solvent is shaken off to theperiphery of the substrate W. The solvent is thereby removed from thesubstrate W and the substrate W is dried (drying processing). After thedrying processing has been performed for a predetermined time, thecontroller 22 controls the spin motor 7 to stop the rotation of thesubstrate W by the spin chuck 2. Further, the controller 22 controls theshielding plate elevating mechanism 9 to move the shielding plate 3 fromthe processing position to the retreat position. Thereafter, thesubstrate W that has been processed is carried out from the spin chuck 2by the transfer robot.

FIG. 6 is a process chart for describing a second processing example ofprocessing a substrate W by the substrate processing apparatus 1according to the first embodiment of the present invention. In thefollowing description, the processing example of processing thesubstrate W having patterns P formed on the front surface, which is thedevice forming surface, shall be described with reference to FIG. 1,FIG. 2, and FIG. 6. In the second processing example, two types ofhydrophobizing agents are supplied to the substrate W. In the secondprocessing example, the steps up to the first hydrophobizationprocessing (S104) are the same as those of the first processing exampleand thus the same reference symbols as those of the first processingexample are attached and description thereof shall be omitted. Thus, inthe following description, the steps performed after the firsthydrophobization processing shall be described.

After the first hydrophobization processing (S104) has been performed, asecond solvent rinsing processing (second solvent rinsing step) ofsupplying the solvent to the substrate W is performed (S107).Specifically, the controller 22 opens the solvent valve 18 to cause thesolvent to be discharged from the central axis nozzle 14 toward thecentral portion of the upper surface of the substrate W whilepositioning the shielding plate 3 at the processing position and furthermaking the substrate W rotate by the spin chuck 2. The solventdischarged from the central axis nozzle 14 is thereby supplied as thesecond solvent to the entire upper surface of the substrate W. Asmentioned above, the solvent is a liquid that can dissolve thehydrophobizing agent and thus by supplying the solvent to the entireupper surface of the substrate W, the first hydrophobizing agentadhering to the substrate W is replaced by the solvent (second solventrinsing processing). Then, when the second solvent rinsing processinghas been performed for a predetermined time, the controller 22 closesthe solvent valve 18 to stop the discharge of the solvent.

Thereafter, a second hydrophobization processing (hydrophobizing step,second hydrophobizing step) of supplying the second hydrophobizing agent(liquid) to the substrate is performed (S108). Specifically, thecontroller 22 controls the second hydrophobizing agent supply unit 17 tocause the second hydrophobizing agent to be discharged from the centralaxis nozzle 14 toward the central portion of the upper surface of thesubstrate W while positioning the shielding plate 3 at the processingposition and further making the substrate W rotate by the spin chuck 2.The second hydrophobizing agent is thereby supplied to the entire uppersurface of the substrate W. As mentioned above, the solvent is a liquidthat can dissolve the hydrophobizing agent and thus by supplying thesecond hydrophobizing agent to the entire upper surface of the substrateW, the solvent adhering to the substrate W is replaced by the secondhydrophobizing agent. The second hydrophobizing agent is thereby made toenter into internal portions of the patterns P and the upper surface ofthe substrate W is thereby hydrophobized (second hydrophobizationprocessing). Then, when the second hydrophobization processing has beenperformed for a predetermined time, the controller 22 controls thesecond hydrophobizing agent supply unit 17 to stop the discharge of thesecond hydrophobizing agent.

Thereafter, a pre-drying rinsing processing (pre-drying rinsing step) ofsupplying the solvent to the substrate W is performed (S109).Specifically, the controller 22 opens the solvent valve 18 to cause thesolvent to be discharged from the central axis nozzle 14 toward thecentral portion of the upper surface of the substrate W whilepositioning the shielding plate 3 at the processing position and furthermaking the substrate W rotate by the spin chuck 2. The solventdischarged from the central axis nozzle 14 is thereby supplied to theentire upper surface of the substrate W. The second hydrophobizing agentadhering to the substrate W is thus replaced by the solvent (pre-dryingrinsing processing). Then, when the pre-drying rinsing processing hasbeen performed for a predetermined time, the controller 22 closes thesolvent valve 18 to stop the discharge of the solvent.

Thereafter, a drying processing (drying step) of drying the substrate Wis performed (S110). Specifically, the controller 22 controls the spinmotor 7 to rotate the substrate W at a high rotation speed (for example,several thousand rpm) with the shielding plate 3 being positioned at theprocessing position. A large centrifugal force thus acts on the solventadhering to the substrate W and the solvent is shaken off to theperiphery of the substrate W. The solvent is thereby removed from thesubstrate W and the substrate W is dried (drying processing). After thedrying processing has been performed for a predetermined time, thecontroller 22 controls the spin motor 7 to stop the rotation of thesubstrate W by the spin chuck 2. Further, the controller 22 controls theshielding plate elevating mechanism 9 to move the shielding plate 3 fromthe processing position to the retreat position. Thereafter, thesubstrate W that has been processed is carried out from the spin chuck 2by the transfer robot.

FIG. 7 is a sectional view of an example of a substrate W processed bythe substrate processing apparatus 1 according to the first embodimentof the present invention.

The substrate W processed by the substrate processing apparatus 1 is,for example, a substrate W having patterns P of a laminated film 32formed thereon. The laminated film 32 includes, for example, a firstfilm 32 a, a second film 32 b, and a third film 32 c. The films 32 a, 32b, and 32 c are laminated in the order of: the third film 32 c, thesecond film 32 b, and the first film 32 a from a side close to the uppersurface of the substrate W itself. That is, the first film 32 acorresponds to being an upper layer film with respect to the second film32 b and the third film 32 c, and the second film 32 b and the thirdfilm 32 c correspond to being lower layer films with respect to thefirst film 32 a. Also, the second film 32 b corresponds to being anupper layer film with respect to the third film 32 c, and the third film32 c corresponds to being a lower layer film with respect to the secondfilm 32 b. The first film 32 a is, for example, any of asilicon-containing film, a nitride film, and a metal film. The sameapplies to each of the second film 32 b and the third film 32 c.

The silicon-containing film is, for example, any of a polysilicon film,an SiO₂ film, an SiN film, a BSG film (an SiO₂ film that containsboron), and a TEOS film (an SiO₂ film formed by the CVD method usingTEOS (tetraethoxysilane)). The SiO₂ film, BSG film, and TEOS film areoxide films.

The nitride film is, for example, an SiN film. The SiN film is also asilicon-containing film.

The metal film is, for example, a film that contains at least one of Ti,W, Cu, and Al. The metal film is, for example, either a TiN film or a Wfilm.

Specific examples of combinations of the first film 32 a, the secondfilm 32 b, and the third film 32 c include “silicon-containing film(first film 32 a), silicon-containing film (second film 32 b), and metalfilm (third film 32 c),” “metal film (first film 32 a),silicon-containing film (second film 32 b), and silicon-containing film(third film 32 c),” “SiN film (first film 32 a), BSG film (second film32 b), and polysilicon film (third film 32 c),” “BSG film (first film 32a), TEOS film (second film 32 b), and polysilicon film (third film 32c),” and “SiN film (first film 32 a), metal film (second film 32 b), andarbitrary film (third film 32 c).” The first film 32 a, the second film32 b, and the third film 32 c are not restricted to these combinationsand may be of other combinations.

A silicon-containing film is hydrophobized by a silicon hydrophobizingagent. Likewise, an oxide film and a nitride film are hydrophobized by asilicon hydrophobizing agent. Also, a metal film is hydrophobized by ametal hydrophobizing agent.

In the following description, specific combinations of the first film 32a, the second film 32 b, and the third film 32 c and specific examplesof the first hydrophobizing agent and the second hydrophobizing agentused for the respective combinations shall be described.

FIG. 8 is a table for describing hydrophobizing agents used in a casewhere the first film 32 a, the second film 32 b, and the third film 32 care a silicon-containing film, a silicon-containing film, and a metalfilm, respectively.

In the case where the first film 32 a, the second film 32 b, and thethird film 32 c are, for example, a silicon-containing film, asilicon-containing film, and a metal film, respectively, a siliconhydrophobizing agent or a metal hydrophobizing agent is used as thefirst hydrophobizing agent in the first processing example. Thesilicon-containing film or the metal film is thus hydrophobized.Although unillustrated, even in a case where the first film 32 a, thesecond film 32 b, and the third film 32 c are a metal film, asilicon-containing film, and a silicon-containing film, respectively,for example, a silicon hydrophobizing agent or a metal hydrophobizingagent is used as the first hydrophobizing agent in the first processingexample.

Meanwhile, in the second processing example, for example, a metalhydrophobizing agent is used as the first hydrophobizing agent and asilicon hydrophobizing agent is used as the second hydrophobizing agent.That is, after the lower layer film (third film 32 c) has beenhydrophobized, the upper layer films (first film 32 a and second film 32b) are hydrophobized, and the substrate W is thus hydrophobized in theorder of the lower layer film and the upper layer films. Thus, in thecase where the first film 32 a, the second film 32 b, and the third film32 c are a metal film, a silicon-containing film, and asilicon-containing film, respectively, in the second processing example,for example, the silicon hydrophobizing agent is used as the firsthydrophobizing agent and the metal hydrophobizing agent is used as thesecond hydrophobizing agent.

When in a case of the substrate W having a silicon-containing film and ametal film, a chlorine-containing hydrophobizing agent (for example, afluorinated alkylchlorosilane) is used as the first hydrophobizing agentor the second hydrophobizing agent, the metal film reacts withhydrochloric acid, which is formed by reaction of the hydrophobizingagent. Thus, in the case of the substrate W having a silicon-containingfilm and a metal film, a hydrophobizing agent that does not containchlorine (for example, the nonchloro hydrophobizing agent mentionedabove) is preferably used as the first hydrophobizing agent or thesecond hydrophobizing agent in processing in both the first processingexample and the second processing example. The reaction of hydrochloricacid and the metal film can thereby be prevented.

FIG. 9 is a table for describing hydrophobizing agents used in a casewhere the first film 32 a, the second film 32 b, and the third film 32 care an SiN film, a BSG film, and a polysilicon film, respectively.

In the case where the first film 32 a, the second film 32 b, and thethird film 32 c are an SiN film, a BSG film, and a polysilicon film,respectively, for example, a silicon hydrophobizing agent is used as thefirst hydrophobizing agent in the first processing example. In the casewhere the silicon hydrophobizing agent is used as the firsthydrophobizing agent, the first film 32 a, the second film 32 b, and thethird film 32 c are hydrophobized. On the other hand, if the metalhydrophobizing agent is used as the first hydrophobizing agent, thehydrophobizing performance is low because all of the first film 32 a,the second film 32 b, and the third film 32 c are silicon-containingfilms. Thus, in the first processing example, the silicon hydrophobizingagent is preferably used as the first hydrophobizing agent.

Meanwhile, in the second processing example, for example, a siliconhydrophobizing agent I is used as the first hydrophobizing agent and asilicon hydrophobizing agent II is used as the second hydrophobizingagent. When the silicon hydrophobizing agent I is supplied to thesubstrate W as the first hydrophobizing agent, the first film 32 a, thesecond film 32 b, and the third film 32 c are hydrophobized. When thesilicon hydrophobizing agent II is thereafter supplied as the secondhydrophobizing agent to the substrate W, the first film 32 a (SiN film)is further hydrophobized. That is, the SiN film is hydrophobized by thesilicon hydrophobizing agent I and thereafter further hydrophobized bythe silicon hydrophobizing agent II of a different type from the siliconhydrophobizing agent I. Thus, after the upper layer film and the lowerlayer films have been hydrophobized, the upper layer film is furtherhydrophobized. Details of the hydrophobization processing by the siliconhydrophobizing agent I and the silicon hydrophobizing agent II shall bedescribed later.

FIG. 10 is a table for describing hydrophobizing agents used in a casewhere the first film 32 a, the second film 32 b, and the third film 32 care an SiN film, a metal film, and an arbitrary film, respectively.

In the case where the first film 32 a, the second film 32 b, and thethird film 32 c are an SiN film, a metal film, and an arbitrary film,respectively, for example, a silicon hydrophobizing agent (preferably anonchloro hydrophobizing agent) or a metal hydrophobizing agent is usedas the first hydrophobizing agent in the first processing example. Inthe case where the silicon hydrophobizing agent is used as the firsthydrophobizing agent, the first film 32 a (SiN film) is hydrophobized.On the other hand, in the case where the metal hydrophobizing agent isused as the first hydrophobizing agent, the second film 32 b (metalfilm) is hydrophobized.

Meanwhile, in the second processing example, for example, a metalhydrophobizing agent is used as the first hydrophobizing agent and asilicon hydrophobizing agent (preferably a nonchloro hydrophobizingagent) is used as the second hydrophobizing agent. When the metalhydrophobizing agent is supplied as the first hydrophobizing agent tothe substrate W, the second film 32 b is hydrophobized. When the siliconhydrophobizing agent is thereafter supplied as the second hydrophobizingagent to the substrate W, the first film 32 a (SiN film) ishydrophobized. The upper layer film is thus hydrophobized after thelower layer film has been hydrophobized.

FIG. 11 is a graph of contact angles of pure water with respect to SiO₂and TiN test pieces that were immersed in a silicon hydrophobizingagent. Also, FIG. 12 is a graph of contact angles of pure water withrespect to SiO₂ and TiN test pieces that were immersed in a metalhydrophobizing agent. Also, FIG. 13 is a graph of contact angles of purewater with respect to SiO₂, TiN, and W test pieces that weresuccessively immersed in the silicon hydrophobizing agent and the metalhydrophobizing agent.

As shown in FIG. 11, the contact angle of pure water with respect to theSiO₂ test piece that was immersed in the silicon hydrophobizing agent isno less than 70 degrees for all immersion times. Also, as shown in FIG.11, the contact angle of pure water with respect to the TiN test piecethat was immersed in the silicon hydrophobizing agent is no more than 20degrees for an immersion time of no more than 2 minutes and no more than30 degrees for an immersion time of no less than 3 minutes.

Meanwhile, as shown in FIG. 12, the contact angle of pure water withrespect to the SiO₂ test piece that was immersed in the metalhydrophobizing agent is approximately 40 degrees for all immersiontimes. Also, as shown in FIG. 12, the contact angle of pure water withrespect to the TiN test piece that was immersed in the metalhydrophobizing agent is approximately 80 degrees for all immersiontimes.

From the measurement values shown in FIG. 11 and FIG. 12, it can beunderstood that although the silicon hydrophobizing agent canhydrophobize a silicon-containing compound (SiO₂) sufficiently, itcannot hydrophobize a metal-containing compound (TiN) sufficiently. Itcan also be understood that although the metal hydrophobizing agent canhydrophobize a metal-containing compound (TiN) sufficiently, it cannothydrophobize a silicon-containing compound (SiO₂) sufficiently.

Meanwhile, as shown in FIG. 13, the contact angles of pure water withrespect to the SiO₂, TiN, and W test pieces that were successivelyimmersed in the silicon hydrophobizing agent and the metalhydrophobizing agent are approximately 80 degrees, approximately 70degrees, and approximately 60 degrees respectively. Thus, by supplyingboth hydrophobizing agents of the silicon hydrophobizing agent and themetal hydrophobizing agent to the substrate W, the substrate W thatincludes a silicon-containing film and a metal film can be hydrophobizedsufficiently.

FIG. 14 is a graph of contact angles before and after rinsing processingof a metal-containing compound that was immersed in a metalhydrophobizing agent. The contact angle before rinsing in FIG. 14 is thecontact angle before the metal-containing compound, which was immersedin an amine having a hydrophobic group as an example of a metalhydrophobizing agent, was rinsed. Also, each of the contact angles afterrinsing in FIG. 14 is the contact angle after the metal-containingcompound immersed in the amine having the hydrophobic group was rinsedby any of a solvent A, a solvent B, and pure water. The solvent A andthe solvent B are solvents of different types. The solvent A is asolvent used as the first solvent and the second solvent in the firstprocessing example and the second processing example. The same appliesto the solvent B.

As shown in FIG. 14, the contact angle of pure water with respect to themetal-containing compound immersed in the amine having the hydrophobicgroup (contact angle before rinsing) is approximately 90 degrees. Whenthe metal-containing compound is rinsed by the solvent A, the contactangle decreases by approximately 10 degrees. Also, when themetal-containing compound is rinsed by the solvent B, the contact angledecreases by approximately 15 degrees. Also, when the metal-containingcompound is rinsed by pure water, the contact angle decreases byapproximately 50 degrees.

From the measurement values shown in FIG. 14, when pure water (a liquidthat contains an OH group) is supplied to the metal-containing compoundimmersed in the amine having the hydrophobic group, the contact angledecreases significantly in comparison to the cases of supplying thesolvent A and the solvent B. Thus, by not supplying pure water to thesubstrate W after supplying the amine having the hydrophobic group tothe substrate W, that is, by maintaining a state where pure water doesnot contact the substrate W, the decrease in the contact angle of purewater with respect to the substrate W can be suppressed or prevented.

FIG. 15 is a schematic diagram of changes in a surface state of SiN whenthe silicon hydrophobizing agent I and the silicon hydrophobizing agentII are successively supplied to SiN.

As mentioned above, SiN is hydrophobized by both the siliconhydrophobizing agent I and the silicon hydrophobizing agent II. Ahydrophobic group of the silicon hydrophobizing agent II is shorter thana hydrophobic group of the silicon hydrophobizing agent I. That is, amolecular weight of the hydrophobic group of the silicon hydrophobizingagent II is less than a molecular weight of the hydrophobic group of thesilicon hydrophobizing agent I. A reactivity of a hydrophobizing agentwith respect to SiN is higher the shorter the hydrophobic group. Thesilicon hydrophobizing agent II is thus higher in reactivity to SiN thanthe silicon hydrophobizing agent I. On the other hand, if the reactivitywith respect to SiN is the same, the contact angle of pure water withrespect to SiN can be increased more the longer the hydrophobic group.The silicon hydrophobizing agent I can thus hydrophobize SiN moreefficiently than the silicon hydrophobizing agent II.

For example, when SiN and SiO₂ are compared, although both aresilicon-containing compounds, SiN is lower in the number of functionalgroups (groups of high reactivity) than SiO₂. Thus, even if the siliconhydrophobizing agent II is supplied to SiN and the functional groups ofSiN and the hydrophobic group of the silicon hydrophobizing agent II arereacted efficiently, the surface of SiN is not hydrophobizedsufficiently because SiN is low in the number of functional groups andthe hydrophobic group of the silicon hydrophobizing agent II is short.That is, the contact angle is not increased sufficiently.

Meanwhile, although the hydrophobic group of the silicon hydrophobizingagent I is long, the silicon hydrophobizing agent I is lower inreactivity with respect to SiN than the silicon hydrophobizing agent II.Thus, even if the silicon hydrophobizing agent I is supplied to SiN, aportion of the functional groups of SiN does not react with thehydrophobic group of the silicon hydrophobizing agent I and thehydrophobicity of SiN thus does not increase sufficiently as a whole.Thus, by supplying both the silicon hydrophobizing agent I and thesilicon hydrophobizing agent II to SiN, both the silicon hydrophobizingagent I and the silicon hydrophobizing agent II can be reacted with SiNto hydrophobize SiN sufficiently.

Especially by supplying the silicon hydrophobizing agent I to SiN andthereafter supplying the silicon hydrophobizing agent II of highreactivity to SiN as shown in FIG. 15, the hydrophobic group of thesilicon hydrophobizing agent I can be reacted with the functional groupsof SiN and the hydrophobic group of the silicon hydrophobizing agent IIcan be reacted with the functional groups of SiN that remain withoutreacting with the hydrophobic group of the silicon hydrophobizing agentI. SiN can thereby be hydrophobized sufficiently. Thus, for an SiN film,it is preferable to supply the silicon hydrophobizing agent I with thelong hydrophobic group and thereafter supply the silicon hydrophobizingagent II with the short hydrophobic group.

FIG. 16 is a schematic sectional view of a substrate W for describing aforce applied to patterns P.

When the substrate W with the patterns P formed thereon is dried, aforce that draws the patterns P toward each other is applied as thesubstrate W dries and the patterns P may thereby collapse. The force Fapplied to the patterns P is expressed, for example, by the followingformula (1).F=(2×σ×H cos θ)/L  (Formula 1)

“σ” is a surface tension of the processing liquid, “θ” is a contactangle, “H” is a height of the patterns P, and “L” is an interval betweenthe patterns P.

From the formula (1), it can be understood that the lower the surfacetension a of the processing liquid, the less the force F applied to thepatterns P. Thus, by lowering the surface tension a of the processingliquid, the force F applied to the patterns P can be decreased tothereby suppress or prevent collapse of the patterns P.

It can also be understood that the force F applied to the patterns Pdecreases the closer the contact angle θ is to 90 degrees. Thus, byhydrophobizing the surface of the substrate W and thereby making thecontact angle θ approach 90 degrees, collapse of the patterns P can besuppressed or prevented.

On the other hand, if the hydrophobization of the surface of thesubstrate W is insufficient, the force F applied to the patterns P isnot reduced sufficiently and collapse of the patterns P cannot besuppressed sufficiently. It is thus preferable to sufficientlyhydrophobize the entire surface of the substrate W to sufficientlysuppress collapse of the patterns P.

In the first processing example and the second processing exampledescribed above, the substrate W is hydrophobized by the hydrophobizingagents (first hydrophobization processing and second hydrophobizationprocessing). The contact angle of the processing liquid with respect tothe substrate W can thereby be made to approach 90 degrees. The forceapplied to the patterns P can thereby be reduced to suppress or preventcollapse of the patterns P.

Also, in the second processing example, a plurality of types of thehydrophobizing agents are supplied to the substrate W (firsthydrophobization processing and second hydrophobization processing).Thus, in the case of processing the substrate W, which has formedthereon the patterns P of the laminated film 32 that includes thesilicon-containing film and the metal film, the entire front surface ofthe substrate W can be hydrophobized sufficiently. Further, in a case ofprocessing a substrate W having an SiN film or other nitride film, thehydrophobicity of the substrate W can be increased sufficiently.Collapse of the patterns P can thereby be suppressed or prevented.

In the first processing example and the second processing example, thesolvent or the hydrophobizing agent and the solvent is or are supplieduntil the substrate W has been dried after having been hydrophobized(from the end of the first hydrophobization processing to the end of thedrying processing). The hydrophobizing agent and the solvent are liquidsthat do not contain water. Thus, in the first processing example and thesecond processing example, the state in which pure water does notcontact the substrate W is maintained until the substrate W has beendried after having been hydrophobized.

As was described with reference to FIG. 14, when, after supplying theamine having the hydrophobic group as an example of the metalhydrophobizing agent to the substrate W that includes the metal film,pure water is supplied to the substrate W, the hydrophobicity of thesubstrate W decreases significantly. Thus, by maintaining the state inwhich pure water does not contact the substrate W until the substrate Whas been dried after having been hydrophobized, the hydrophobicity ofthe substrate W is prevented from significantly decreasing in the casewhere the amine having the hydrophobic group is supplied to thesubstrate W. Collapse of the patterns P can thereby be suppressed orprevented.

Also, by maintaining the state in which pure water does not contact thesubstrate W until the substrate W has been dried after having beenhydrophobized, formation of watermarks can be suppressed or prevented.

Also, in the second processing example, the upper layer films arehydrophobized by the second hydrophobizing agent after the lower layerfilm has been hydrophobized by the first hydrophobizing agent or afterthe lower layer film and the upper layer films have been hydrophobizedby the first hydrophobizing agent. For example, if the hydrophobizingagent is further supplied to the substrate W after the upper layer filmshave been hydrophobized, the hydrophobizing agent may not be suppliedsufficiently to the lower layer film because the upper layer films havealready been hydrophobized. Thus, by supplying the second hydrophobizingagent, which hydrophobizes the upper layer films, to the substrate Wafter the lower layer film has been hydrophobized or after the lowerlayer film and the upper layer films have been hydrophobized, the upperlayer films and the lower layer film can be hydrophobized sufficiently.The substrate W can thereby be hydrophobized sufficiently.

Also, in the first processing example and the second processing example,pure water, which is an example of a rinsing liquid, is supplied to thesubstrate W (water rinsing processing). Thereafter, the solvent issupplied as the first solvent to the substrate W (first solvent rinsingprocessing). The pure water adhering to the substrate W is therebyreplaced by the solvent. The first hydrophobizing agent and the secondhydrophobizing agent are thus supplied to the substrate W in a statewhere pure water is removed. The first hydrophobizing agent and thesecond hydrophobizing agent are thus prevented from contacting purewater. Thus, in a case where hydrophobizing agents that decrease inactivity by contacting water are used as the first hydrophobizing agentand the second hydrophobizing agent, decreases in the activities of thefirst hydrophobizing agent and the second hydrophobizing agent areprevented. The substrate W can thereby be hydrophobized sufficiently.

Also, in the second processing example, the solvent that can dissolvethe first hydrophobizing agent and the second hydrophobizing agent issupplied as the second solvent to the substrate W after performing thefirst hydrophobization processing and before performing the secondhydrophobization processing (second solvent rinsing processing). In acase where the first hydrophobizing agent and the second hydrophobizingagent do not readily mix together, even if the second hydrophobizingagent is supplied to the substrate W in the state where the firsthydrophobizing agent is adhering to the substrate W, the firsthydrophobizing agent adhering to the substrate W cannot readily bereplaced by the second hydrophobizing agent. The second hydrophobizingagent thus does not contact the front surface of the substrate Wsufficiently.

Meanwhile, the solvent (second solvent) can dissolve the firsthydrophobizing agent and the second hydrophobizing agent. Thus, bysupplying the solvent to the substrate after performing the firsthydrophobization processing, the first hydrophobizing agent adhering tothe substrate W can be replaced by the solvent and the firsthydrophobizing agent can thereby be removed from the substrate W. Bythen supplying the second hydrophobizing agent to the substrate W afterthe second solvent rinsing processing has been performed, the solventadhering to the substrate W can be replaced by the second hydrophobizingagent and the solvent can thereby be removed from the substrate W. Thus,even in the case where the first hydrophobizing agent and the secondhydrophobizing agent do not readily mix together, the firsthydrophobizing agent adhering to the substrate W can be replaced by thesecond hydrophobizing agent. The second hydrophobizing agent can therebybe made to react with the substrate W and the substrate W can behydrophobized by the second hydrophobizing agent.

Also, in the first processing example and the second processing example,the solvent is supplied to the substrate W in the pre-drying rinsingprocessing. Thereafter, the solvent adhering to the substrate W isremoved and the substrate W is dried. The solvent supplied to thesubstrate W in the pre-drying rinsing processing is lower in surfacetension than water. Collapse of the patterns P can thus be suppressed orprevented more than in a case where pure water is supplied to thesubstrate W in the pre-drying rinsing processing. Further, the solventsupplied to the substrate W in the pre-drying rinsing processing islower in boiling point than water. The substrate W can thus be driedmore rapidly than in the case where pure water is supplied to thesubstrate W in the pre-drying rinsing processing.

Also, in the first processing example and the second processing example,the first hydrophobizing agent and the second hydrophobizing agent thathave been diluted by the diluting solvent are supplied to the substrateW. The diluting solvent can dissolve the solvent used as the firstsolvent and the second solvent. Thus, by the first hydrophobizing agentand the second hydrophobizing agent being diluted by the dilutingsolvent, compatibilities of the first hydrophobizing agent and thesecond hydrophobizing agent with the first solvent and the secondsolvent are increased. The solvent (first solvent and second solvent)adhering to the substrate W can thus be replaced readily by the firsthydrophobizing agent and the second hydrophobizing agent.

Also, in the first processing example and the second processing example,the hydrophobizing agent (first hydrophobizing agent and secondhydrophobizing agent) and the diluting solvent are mixed inside thecollective pipe 31. That is, each of the first hydrophobizing agent andthe second hydrophobizing agent is diluted by the diluting solventimmediately before being supplied to the substrate W. Thus, in a casewhere hydrophobizing agents that gradually decrease in activity by beingdiluted by the diluting solvent are used as the first hydrophobizingagent and the second hydrophobizing agent, the activities of the firsthydrophobizing agent and the second hydrophobizing agent are preventedfrom significantly decreasing. The substrate W can thereby behydrophobized sufficiently.

[Second Embodiment]

FIG. 17 is a schematic view of a general arrangement of a substrateprocessing apparatus 201 according to a second embodiment of the presentinvention. FIG. 18 is a schematic view of a general arrangement of afirst hydrophobizing agent supply unit 216 according to the secondembodiment of the present invention. In FIG. 17 and FIG. 18, componentportions that are equivalent to the respective portions shown in FIG. 1to FIG. 16 described above are provided with the same reference symbolsas in FIG. 1, etc., and description thereof shall be omitted.

A main point of difference of the second embodiment with respect to thefirst embodiment is that the substrate processing apparatus 201 includesthe first hydrophobizing agent supply unit 216 (hydrophobizing agentsupply unit, first hydrophobizing agent supply unit) and a secondhydrophobizing agent supply unit 217 (hydrophobizing agent supply unit,second hydrophobizing agent supply unit) that supply a vapor of thefirst hydrophobizing agent and a vapor of the second hydrophobizingagent, respectively, as shown in FIG. 17. The general arrangement of thefirst hydrophobizing agent supply unit 216 and the general arrangementof the second hydrophobizing agent supply unit 217 are the same, andthus the general arrangement of the first hydrophobizing agent supplyunit 216 shall be described below.

As shown in FIG. 18, the first hydrophobizing agent supply unit 216includes the first tank 23 storing the first hydrophobizing agent(liquid) and the second tank 24 storing a diluting solvent (liquid).Further, the first hydrophobizing agent supply unit 216 includes aheater 233 interposed in the collective pipe 31 and a carrier gas supplypipe 235 having a valve 234 interposed therein. The carrier gas supplypipe 235 is connected to the collective pipe 31. A temperature of theheater 233 is controlled by the controller 22 (see FIG. 3). Also,opening and closing of the valve 234 are controlled by the controller22. When the valve 234 is opened, a carrier gas is supplied to thecollective pipe 31. Nitrogen gas, argon gas, and other inert gases canbe cited as examples of the carrier gas.

The diluting solvent is the same as that of the first embodiment. In thesecond embodiment, for example, a solvent that contains an HFE is usedas the diluting solvent. The HFE is lower in boiling point than water.Thus, by diluting the first hydrophobizing agent by this dilutingsolvent, the boiling point of the diluted first hydrophobizing agent canbe lowered. The first hydrophobizing agent that has been diluted canthus be vaporized readily. Also, the HFE is nonflammable. The controller22 controls the opening degrees of the first flow regulating valve 28and the second flow regulating valve 30 so that the diluted firsthydrophobizing agent is nonflammable. Measures for preventing explosionof the substrate processing apparatus 201 are thus made unnecessary.

The controller 22 opens the first valve 27, the second valve 29, and thevalve 234 and further makes the collective pipe 31 be heated by theheater 233. By opening the first valve 27 and the second valve 29, thefirst hydrophobizing agent (liquid) and the diluting solvent (liquid)are supplied to the collective pipe 31. The first hydrophobizing agentand the diluting agent supplied to the collective pipe 31 are mixedinside the collective pipe 31 and thereafter heated by the heater 233.The mixed solution of the first hydrophobizing agent and the dilutingsolvent is thereby vaporized and the liquid of the diluted firsthydrophobizing agent changes to a vapor. The vapor of the firsthydrophobizing agent produced inside the collective pipe 31 is then madeto flow toward the central axis nozzle 14 by the carrier gas suppliedfrom the carrier gas supply pipe 235 to the collective pipe 31. Thevapor of the first hydrophobizing agent is thereby discharged from thecentral axis nozzle 14.

As shown in FIG. 17, the controller 22 causes the vapor of the firsthydrophobizing agent and the vapor of the second hydrophobizing agent tobe discharged from the central axis nozzle 14 with the shielding plate 3being positioned at the processing position. The vapor of thehydrophobizing agent discharged from the central axis nozzle 14 spreadsoutward between the shielding plate 3 and the substrate W and isexhausted from between the shielding plate 3 and the substrate W. Thespace between the shielding plate 3 and the substrate W is therebyfilled with the vapor of the hydrophobizing agent. Also, the vapor ofthe hydrophobizing agent discharged from the central axis nozzle 14flows outward along the upper surface of the substrate W. The vapor ofthe hydrophobizing agent is thereby supplied to the entire upper surfaceof the substrate W. While the vapor of the hydrophobizing agent is beingdischarged from the central axis nozzle 14, the substrate W held by thespin chuck 2 may be rotated about the vertical rotational axis passingthrough the center of the substrate W or may be held in a non-rotatingstate.

FIG. 19 is a process chart for describing a third processing example ofprocessing a substrate W by the substrate processing apparatus 201according to the second embodiment of the present invention. In thefollowing description, the processing example of processing thesubstrate W having the patterns P formed on the front surface, which isthe device forming surface, shall be described with reference to FIG. 17and FIG. 19. In the third processing example, the steps up to the firstsolvent rinsing processing (S103) are the same as those of the firstprocessing example and thus the same reference symbols as those of thefirst processing example are attached and description thereof shall beomitted. Thus, in the following description, the steps performed afterthe first solvent rinsing processing shall be described.

After the first solvent rinsing processing (S103) has been performed, afirst hydrophobization processing (hydrophobizing step, vapor supplystep, first hydrophobizing step, first vapor supply step) of supplyingthe first hydrophobizing agent (vapor) to the substrate W is performed(S204). Specifically, the controller 22 controls the firsthydrophobizing agent supply unit 216 to cause the vapor of the firsthydrophobizing agent to be discharged from the central axis nozzle 14toward the central portion of the upper surface of the substrate W withthe shielding plate 3 being positioned at the processing position. Thesolvent adhering to the substrate W is removed from the substrate Wwhile dissolving into the vapor of the first hydrophobizing agent thatflows outward along the upper surface of the substrate W. Also, by thevapor of the first hydrophobizing agent flowing outward along the uppersurface of the substrate W, the vapor of the first hydrophobizing agentis supplied to the entire upper surface of the substrate W and the vaporof the first hydrophobizing agent enters into the internal portions ofthe patterns P. The upper surface of the substrate W is therebyhydrophobized (first hydrophobization processing). Then, when the firsthydrophobization processing has been performed for a predetermined time,the controller 22 controls the first hydrophobizing agent supply unit216 to stop the discharge of the vapor of the first hydrophobizingagent.

Thereafter, a drying processing (drying step, vaporizing step) of dryingthe substrate W is performed (S205). Specifically, the controller 22makes the liquid droplets of the first hydrophobizing agent adhering tothe upper surface of the substrate W vaporize to thereby dry thesubstrate W (drying processing). The controller 22 may make thesubstrate W rotate by the spin chuck 2 to make the liquid droplets ofthe first hydrophobizing agent vaporize by an air flow resulting fromthe rotation of the substrate W or may make the liquid droplets of thefirst hydrophobizing agent vaporize naturally while keeping thesubstrate W still. Also, the controller 22 may make the liquid dropletsof the first hydrophobizing agent vaporize while making the transferrobot transfer the substrate W.

FIG. 20 is a process chart for describing a fourth processing example ofprocessing a substrate W by the substrate processing apparatus 201according to the second embodiment of the present invention. In thefollowing description, the processing example of processing thesubstrate W having the patterns P formed on the front surface, which isthe device forming surface, shall be described with reference to FIG. 17and FIG. 20. In the fourth processing example, vapors of two types ofhydrophobizing agents are supplied to the substrate W. In the fourthprocessing example, the steps up to the first hydrophobizationprocessing (S204) are the same as those of the third processing exampleand thus the same reference symbols as those of the third processingexample are attached and description thereof shall be omitted. Thus, inthe following description, the steps performed after the firsthydrophobization processing shall be described.

After the first hydrophobization processing (S204) has been performed, asecond solvent rinsing processing (second solvent rinsing step) ofsupplying the solvent to the substrate W is performed (S206).Specifically, the controller 22 opens the solvent valve 18 to cause thesolvent to be discharged from the central axis nozzle 14 toward thecentral portion of the upper surface of the substrate W whilepositioning the shielding plate 3 at the processing position and furthermaking the substrate W rotate by the spin chuck 2. The solventdischarged from the central axis nozzle 14 is thereby supplied as thesecond solvent to the entire upper surface of the substrate W. Asmentioned above, the solvent is a liquid that can dissolve thehydrophobizing agent and thus by supplying the solvent to the entireupper surface of the substrate W, the liquid droplets of the firsthydrophobizing agent adhering to the substrate W are replaced by thesolvent (second solvent rinsing processing). Then, when the secondsolvent rinsing processing has been performed for a predetermined time,the controller 22 closes the solvent valve 18 to stop the discharge ofthe solvent.

After the second solvent rinsing step (S206) has been performed, asecond hydrophobization processing (hydrophobizing step, vapor supplystep, second hydrophobizing step, second vapor supply step) of supplyingthe second hydrophobizing agent (vapor) to the substrate W is performed(S207). Specifically, the controller 22 controls the secondhydrophobizing agent supply unit 217 to cause the vapor of the secondhydrophobizing agent to be discharged from the central axis nozzle 14toward the central portion of the upper surface of the substrate W withthe shielding plate 3 being positioned at the processing position. Bythe vapor of the second hydrophobizing agent flowing outward along theupper surface of the substrate W, the vapor of the second hydrophobizingagent is supplied to the entire upper surface of the substrate W and thevapor of the second hydrophobizing agent enters into the internalportions of the patterns P. The upper surface of the substrate W isthereby hydrophobized (second hydrophobization processing). Then, whenthe second hydrophobization processing has been performed for apredetermined time, the controller 22 controls the second hydrophobizingagent supply unit 217 to stop the discharge of the vapor of the secondhydrophobizing agent.

Thereafter, a drying processing (drying step, vaporizing step) of dryingthe substrate W is performed (S208). Specifically, the controller 22makes the liquid droplets of the second hydrophobizing agent adhering tothe upper surface of the substrate W vaporize to thereby dry thesubstrate W (drying processing). The controller 22 may rotate thesubstrate W by the spin chuck 2 to make the liquid droplets of thesecond hydrophobizing agent vaporize by an air flow resulting from therotation of the substrate W or may make the liquid droplets of thesecond hydrophobizing agent vaporize naturally while keeping thesubstrate W still. Also, the controller 22 may make the liquid dropletsof the second hydrophobizing agent vaporize while making the transferrobot transfer the substrate W.

The third processing example corresponds to the first processing exampledescribed above and the fourth processing example corresponds to thesecond processing example described above. That is, the substrate Wprocessed by the substrate processing apparatus 201 is, for example, thesubstrate W having the patterns P of the laminated film 32 formedthereon (see FIG. 7). In the case where the first film 32 a, the secondfilm 32 b, and the third film 32 c are, for example, asilicon-containing film, a silicon-containing film, and a metal film,respectively (see FIG. 8), a silicon hydrophobizing agent or a metalhydrophobizing agent is used as the first hydrophobizing agent in thethird processing example. Also, in the case where the first film 32 a,the second film 32 b, and the third film 32 c are, for example, asilicon-containing film, a silicon-containing film, and a metal film,respectively (see FIG. 8), for example, a metal hydrophobizing agent isused as the first hydrophobizing agent and a silicon hydrophobizingagent is used as the second hydrophobizing agent in the fourthprocessing example. The same applies to other combinations of the firstfilm 32 a, the second film 32 b, and the third film 32 c.

As described above, with the second embodiment, the vapor of thehydrophobizing agent is supplied to the substrate W in both the thirdprocessing example and the fourth processing example. A portion of thevapor of the hydrophobizing agent supplied to the substrate W changes toliquid droplets and adheres to the substrate W. However, the liquiddroplets of the hydrophobizing agent vaporize and are removed from thesubstrate W in a short time. The hydrophobizing agent thus does not haveto be rinsed off by a solvent as in the first processing example and thesecond processing example. That is, the pre-drying rinsing processingdoes not have to be performed. The processing time for the substrate Wcan thereby be shortened.

Also, in the fourth processing example, the second solvent rinsingprocessing is performed after performing the first hydrophobizationprocessing and before performing the second hydrophobization processing.If at the end of the first hydrophobization processing, the substrate Wdries due to the liquid droplets of the first hydrophobizing agentvaporizing from the substrate W, the patterns P may collapse due toinsufficient lowering of the hydrophobicity of the substrate W. Thesubstrate W is thus prevented from drying by performing the secondsolvent rinsing processing of supplying the solvent to the substrate Wbefore the liquid droplets of the first hydrophobizing agent are removedby vaporization. By thereafter supplying the vapor of the secondhydrophobizing agent, the solvent adhering to the substrate W isreplaced by the second hydrophobizing agent and the secondhydrophobization processing is performed.

Also, in the third processing example and the fourth processing example,the state in which pure water does not contact the substrate W ismaintained until the substrate W has been dried after having beenhydrophobized (from the end of the first hydrophobization processing tothe end of the drying processing). The hydrophobicity of the substrate Wis thus prevented from significantly decreasing in the case where anamine having the hydrophobic group, which is an example of a metalhydrophobizing agent, is supplied to the substrate W that includes ametal film. Collapse of the patterns P can thereby be suppressed orprevented.

Also, by maintaining the state in which pure water does not contact thesubstrate W until the substrate W has been dried after having beenhydrophobized, formation of watermarks can be suppressed or prevented.

[Third Embodiment]

FIG. 21 and FIG. 22 are schematic views of a general arrangement of asubstrate processing apparatus 301 according to a third embodiment ofthe present invention, with each figure showing a different state.

The substrate processing apparatus 301 is a single substrate processingtype substrate processing apparatus that processes a semiconductor waferor other substrate W one at a time by a chemical solution, a rinsingliquid, and other processing liquids. The substrate processing apparatus301 includes a spin chuck 302 (substrate holding unit) that horizontallyholds and rotates the substrate W, a shielding plate 303 disposed abovethe spin chuck 302, and a processing liquid supply mechanism thatsupplies the processing liquids to the substrate W held by the spinchuck 302.

The spin chuck 302 is, for example, a gripping type chuck that grips andholds the substrate W. The spin chuck 302 includes, for example, adisk-shaped spin base 304 that is disposed horizontally, a plurality ofgripping members 305 disposed on the spin base 304, and a spin motor 306(drying unit) coupled to the spin base 304. The spin chuck 302 can gripthe substrate W from the periphery by putting the respective grippingmembers 305 in contact with the peripheral end surface of the substrateW. Further, the spin chuck 302 can rotate the substrate W about thevertical rotational axis passing through a center of the substrate W byimparting a driving force of the spin motor 306 to the spin base 304while holding the substrate W. The spin chuck 302 is not restricted to agripping type chuck and may be a vacuum type chuck that suctions andholds a lower surface (rear surface) of the substrate W.

Also, the shielding plate 303 has, for example, a disk shape. A diameterof the shielding plate 303 is, for example, substantially the same asthe diameter of the substrate W or slightly greater than the diameter ofthe substrate W. The shielding plate 303 is disposed so that a lowersurface of the shielding plate 303 is horizontal. Further, the shieldingplate 303 is disposed so that a central axis of the shielding plate 303is positioned along the rotational axis of the spin chuck 302. The lowersurface of the shielding plate 303 faces the upper surface of thesubstrate W held by the spin chuck 302. The shielding plate 303 iscoupled in the horizontal posture to a lower end of a support shaft 307.The shielding plate 303 and the support shaft 307 are raised and loweredin the vertical direction by a shielding plate elevating mechanism 308.The shielding plate elevating mechanism 308 raises and lowers theshielding plate 303 between a processing position (position shown inFIG. 22) at which the lower surface of the shielding plate 303 is setclose to the upper surface of the substrate W held by the spin chuck 302and a retreat position (position shown in FIG. 21) set above theprocessing position.

The processing liquid supply mechanism includes a chemical solutionnozzle 309, a chemical solution supply pipe 310, and a chemical solutionvalve 311. The chemical solution supply pipe 310 is connected to thechemical solution nozzle 309. The chemical solution valve 311 isinterposed in the chemical solution supply pipe 310. When the chemicalsolution valve 311 is opened, a chemical solution is supplied from thechemical solution supply pipe 310 to the chemical solution nozzle 309.Also, when the chemical solution valve 311 is closed, the supply of thechemical solution from the chemical solution supply pipe 310 to thechemical solution nozzle 309 is stopped. The chemical solution nozzle309 is coupled to a nozzle moving mechanism (not shown). The nozzlemoving mechanism moves the chemical solution nozzle 309 between aprocessing position (position shown in FIG. 21) set above the spin chuck302 and a retreat position (position shown in FIG. 22) at which thechemical solution nozzle 309 is retracted from above the spin chuck 302.The processing position is set so that the chemical solution dischargedfrom the chemical solution nozzle 309 is supplied to the central portionof the upper surface of the substrate W held by the spin chuck 302 (seeFIG. 21).

Also, the processing liquid supply mechanism includes a solvent nozzle312 (first solvent supply unit), a first solvent supply pipe 313, afirst solvent valve 314, and an ultrasonic transducer 315 (physicalforce applying unit, vibration applying unit). The first solvent supplypipe 313 is connected to the solvent nozzle 312. The first solvent valve314 is interposed in the first solvent supply pipe 313. When the firstsolvent valve 314 is opened, a first solvent (liquid) is supplied fromthe first solvent supply pipe 313 to the solvent nozzle 312. Also, whenthe first solvent valve 314 is closed, the supply of the first solventfrom the first solvent supply pipe 313 to the solvent nozzle 312 isstopped. Vibration of the ultrasonic transducer 315 is applied to thefirst solvent discharged from the solvent nozzle 312. The solvent nozzle312 is coupled to a nozzle moving mechanism (not shown). The nozzlemoving mechanism moves the solvent nozzle 312 between a processingposition set above the spin chuck 302 and a retreat position (positionshown in FIG. 21 and FIG. 22) at which the solvent nozzle 312 isretracted from above the spin chuck 302. The processing position is setso that the first solvent discharged from the solvent nozzle 312 issupplied to the central portion of the upper surface of the substrate Wheld by the spin chuck 302.

Also, the processing liquid supply mechanism includes a central axisnozzle 316 (rinsing liquid supply unit, first solvent supply unit,hydrophobizing agent supply unit, water-soluble solvent supply unit,non-contact state maintaining unit, drying agent supply unit) and aprocessing liquid supply pipe 317. The central axis nozzle 316 isdisposed along the central axis of the shielding plate 303. The centralaxis nozzle 316 extends vertically in an interior of the support shaft307. The central axis nozzle 316 is raised and lowered along with theshielding plate 303 and the support shaft 307. The processing liquidsupply pipe 317 is connected to the central axis nozzle 316 above theshielding plate 303. For example, a hydrophobizing agent, the firstsolvent, a water-soluble solvent, a drying agent, a rinsing liquid, andother processing liquids are supplied from the processing liquid supplypipe 317 to the central axis nozzle 316. The processing liquid suppliedto the central axis nozzle 316 is discharged downward from a dischargeport disposed at a lower end of the central axis nozzle 316. Theprocessing liquid discharged from the central axis nozzle 316 passesthrough a through-hole (not shown) that passes vertically through acentral portion of the shielding plate 303 and is discharged downwardfrom a central portion of the lower surface of the shielding plate 303as shown in FIG. 22. The processing liquid is thereby supplied to thecentral portion of the upper surface of the substrate W.

The processing liquid supply mechanism includes a hydrophobizing agentsupply unit 318, a second solvent supply pipe 320 having a secondsolvent valve 319 interposed therein, a water-soluble solvent supplypipe 322 having a water-soluble solvent valve 321 interposed therein, adrying agent supply pipe 324 having a drying agent valve 323 interposedtherein, and a rinsing liquid supply pipe 326 having a rinsing liquidvalve 325 interposed therein. The processing liquid supply pipe 317 isconnected to the hydrophobizing agent supply unit 318, the secondsolvent supply pipe 320, the rinsing liquid supply pipe 326, and thedrying agent supply pipe 324. The hydrophobizing agent (liquid) issupplied from the hydrophobizing agent supply unit 318 to the processingliquid supply pipe 317. Also, when the second solvent valve 319 isopened, the first solvent (liquid) is supplied from the second solventsupply pipe 320 to the processing liquid supply pipe 317. Also, when thewater-soluble solvent valve 321 is opened, a water-soluble solvent(liquid) is supplied from the water-soluble solvent supply pipe 322 tothe processing liquid supply pipe 317. Also, when the drying agent valve323 is opened, a drying agent (liquid) is supplied from the drying agentsupply pipe 324 to the processing liquid supply pipe 317. Also, when therinsing liquid valve 325 is opened, a rinsing liquid (pure water in FIG.21 and FIG. 22) is supplied from the rinsing liquid supply pipe 326 tothe processing liquid supply pipe 317.

The rinsing liquid is a liquid that contains water. The rinsing liquidis, for example, any of pure water, carbonated water, electrolyzed ionwater, hydrogen water, ozone water, or aqueous hydrochloric acid ofdilute concentration (for example, about 10 to 100 ppm).

The hydrophobizing agent is a metal hydrophobizing agent thathydrophobizes a metal. The hydrophobizing agent is a hydrophobizingagent of a high degree of coordination. That is, the hydrophobizingagent is a solvent that hydrophobizes a metal mainly by coordinationbonds. The hydrophobizing agent contains, for example, at least one ofan amine having a hydrophobic group and an organosilicon compound.

The first solvent is a liquid that does not contain a hydroxyl group.That is, the first solvent is a solvent made of a compound that does notcontain a hydroxyl group. The first solvent is capable of dissolving thehydrophobizing agent. The first solvent does not contain water and ispreferably lower in surface tension than water. The first solvent is aketone type solvent or an ether type solvent. PGMEA and acetone can becited as specific examples of the first solvent. The ketone type orether type solvent is high in solubility of the hydrophobizing agent,and when the hydrophobizing agent is mixed in the ketone type or ethertype solvent, the hydrophobizing agent disperses sufficiently in theketone type or ether type solvent. On the other hand, an alcohol typesolvent is low in solubility of the hydrophobizing agent, and even ifthe hydrophobizing agent is mixed in an alcohol type solvent, thehydrophobizing agent does not disperse sufficiently in the alcohol typesolvent.

The water-soluble solvent is capable of dissolving water. Thewater-soluble solvent may contain water. The water-soluble solvent ishigher in solubility in water than the first solvent and the secondsolvent. Put in another way, the water-soluble solvent is higher inwater solubility than the first solvent and the second solvent. Thefirst solvent is capable of dissolving the water-soluble solvent.Alcohols, PGMEA, EGMEA, and mixed solutions of a fluorine-based solventand an alcohol can be cited as specific examples of the water-solublesolvent. The alcohol contains, for example, at least one of methylalcohol, ethanol, propyl alcohol, and IPA. The fluorine-based solventcontains, for example, at least one of an HFE and an HFC.

The drying agent is a solvent that does not contain water. The dryingagent is lower in boiling point than water. Further, the drying agent iscapable of dissolving the hydrophobizing agent. The drying agent ispreferably lower in surface tension than water. Alcohols and mixedsolutions of a fluorine-based solvent and an alcohol can be cited asspecific examples of the drying agent.

FIG. 23 is a block diagram for describing an electrical arrangement ofthe substrate processing apparatus 301 according to the third embodimentof the present invention.

As shown in FIG. 23, the substrate processing apparatus 301 includes acontroller 327 (controller). The spin motor 306, the shielding plateelevating mechanism 308, and the hydrophobizing agent supply unit 318are controlled by the controller 327. Also, opening and closing of therespective valves included in the substrate processing apparatus 301 arecontrolled by the controller 327. As shown in FIG. 21, the controller327 positions the chemical solution nozzle 309 or the solvent nozzle 312at the processing position and causes a processing liquid to bedischarged from the chemical solution nozzle 309 or the solution nozzle312 in a state where the substrate W is rotated by the spin chuck 302 (astate where a processing liquid is discharged from the chemical solutionnozzle 309 is shown in FIG. 21). The processing liquid discharged fromthe chemical solution nozzle 309 or the solvent nozzle 312 is suppliedto the central portion of the upper surface of the substrate W held bythe spin chuck 302. The processing liquid supplied to the centralportion of the upper surface of the substrate W receives a centrifugalforce due to rotation of the substrate W and spreads outward along thesubstrate W. The processing liquid is thereby supplied to the entireupper surface of the substrate W and the substrate W is processed by theprocessing liquid.

On the other hand, as shown in FIG. 22, the controller 327 positions theshielding plate 303 at the processing position and causes a processingliquid to be discharged from the central axis nozzle 316 while thesubstrate W is being rotated by the spin chuck 302. The processingliquid discharged from the central axis nozzle 316 is supplied to thecentral portion of the upper surface of the substrate W held by the spinchuck 302. The processing liquid supplied to the central portion of theupper surface of the substrate W receives the centrifugal force due torotation of the substrate W and spreads outward along the substrate W.The processing liquid is thereby supplied to the entire upper surface ofthe substrate W and the substrate W is processed by the processingliquid. Also, the processing liquid that is shaken off to the peripheryof the substrate W is suppressed or prevented from splashing back andadhering to the substrate W because the processing liquid is supplied tothe substrate W with the lower surface of the shielding plate 303 beingset close to the upper surface of the substrate W.

FIG. 24 is a schematic view of a general arrangement of thehydrophobizing agent supply unit 318 according to the third embodimentof the present invention.

The hydrophobizing agent supply unit 318 includes a hydrophobizing agenttank 328 storing a stock solution of the hydrophobizing agent and asecond solvent tank 329 storing a second solvent (liquid) as a dilutingsolvent. Further, the hydrophobizing agent supply unit 318 includes afirst pipe 330 connected to the hydrophobizing agent tank 328, a secondpipe 331 connected to the second solvent tank 329, a first pump 332, afirst valve 333 and a first flow regulating valve 334 interposed in thefirst pipe 330, a second pump 335, a second valve 336, and a second flowregulating valve 337 interposed in the second pipe 331, and a collectivepipe 338 connected to the first pipe 330 and the second pipe 331. Amixed solution (stock solution) of 100% hydrophobizing agent and thesecond solvent is stored in the hydrophobizing agent tank 328.

The stock solution of the hydrophobizing agent stored in thehydrophobizing agent tank 328 is sucked into the first pipe 330 by asuction force of the first pump 332. Likewise, the second solvent storedin the second solvent tank 329 is sucked into the second pipe 331 by asuction force of the second pump 335. The stock solution of thehydrophobizing agent stored in the hydrophobizing agent tank 328 mayinstead be supplied into the first pipe 330 by raising an air pressureinside the hydrophobizing agent tank 328 by supplying a gas into thehydrophobizing agent tank 328. The same applies to the second solventstored in the second solvent tank 329. The collective pipe 338 isconnected to the processing liquid supply pipe 317 (see FIG. 21 and FIG.22). Opening degrees of the first flow regulating valve 334 and thesecond flow regulating valve 337 are controlled by the controller 327.The controller 327 controls the opening degrees of the first flowregulating valve 334 and the second flow regulating valve 337 so thatthe stock solution of the hydrophobizing agent and the second solventare supplied, for example, at fixed proportions to the collective pipe338. A hydrophobizing agent (mixed solution of the hydrophobizing agentstock solution and the second solvent) of a fixed concentration is thussupplied to the processing liquid supply pipe 317.

The second solvent is a liquid that does not contain a hydroxyl group.That is, the second solvent is a solvent made of a compound that doesnot contain a hydroxyl group. The second solvent is capable ofdissolving the hydrophobizing agent. The second solvent does not containwater and is preferably lower in surface tension than water. The secondsolvent is a ketone type solvent or an ether type solvent. PGMEA andacetone can be cited as specific examples of the second solvent. Thesecond solvent may be the same type of solvent as the first solvent ormay be a different type of solvent from the first solvent.

When the controller 327 opens the first valve 333, the hydrophobizingagent stock solution stored in the hydrophobizing agent tank 328 issupplied to the collective pipe 338 at a flow rate in accordance withthe opening degree of the first flow regulating valve 334. Likewise,when the controller 327 opens the second valve 336, the second solventstored in the second solvent tank 329 is supplied to the collective pipe338 at a flow rate in accordance with the opening degree of the secondflow regulating valve 337. The hydrophobizing agent stock solution andthe second solvent are thereby mixed inside the collective pipe 338. Thehydrophobizing agent stock solution thus dissolves in the second solventand the hydrophobizing agent stock solution is diluted. The dilutedhydrophobizing agent stock solution, that is, the hydrophobizing agentis supplied from the collective pipe 338 to the processing liquid supplypipe 317 and is discharged from the central axis nozzle 316. That is,the hydrophobizing agent stock solution and the second solvent are mixedin a flow path of the hydrophobizing agent leading from thehydrophobizing agent tank 328 to the substrate W held by the spin chuck302, and the hydrophobizing agent stock solution and the second solventthat are mixed are supplied to the substrate W. The first pipe 330, thecollective pipe 338, the processing liquid supply pipe 317, and thecentral axis nozzle 316 thus make up a portion of the flow path of thehydrophobizing agent.

FIG. 25 is a process chart for describing a processing example ofprocessing a substrate W by the substrate processing apparatus 301according to the third embodiment of the present invention. Theprocessing example of processing the substrate W having patterns P (seeFIG. 26) formed on the front surface, which is the device formingsurface, shall be described below. The patterns P include, for example,a plurality of cylinders (recess portions) formed by metal films M (seeFIG. 26). The cylinders S form electrodes of a capacitor provided in aDRAM (dynamic random access memory). Each cylinder S forms a bottomedcylindrical recess portion that is recessed in a thickness direction ofthe substrate W. In the following description, “upper surface (frontsurface) of the substrate W” includes the upper surface (front surface)of the substrate W itself and surfaces of the patterns P.

An unprocessed substrate W is transferred by an unillustrated transferrobot and is placed on the spin chuck 302, for example, with the frontsurface that is the device forming surface faced upward. The controller327 then makes the spin chuck 302 hold the substrate W. When thesubstrate W is being transferred onto the spin chuck 302, the controller327 positions the chemical solution nozzle 309, the solvent nozzle 312,and the shielding plate 303 at the respective retreat positions toprevent the transfer robot and the substrate W from colliding with thechemical solution nozzle 309, the solvent nozzle 312, and the shieldingplate 303.

Thereafter, a chemical solution processing of supplying the chemicalsolution to the substrate W is performed (S301). Specifically, thecontroller 327 makes the chemical solution nozzle 309 move from theretreat position to the processing position with the shielding plate 303being positioned at the retreat position. Also, the controller 327controls the spin motor 306 to rotate the substrate W held by the spinchuck 302. The controller 327 then opens the chemical solution valve 311to cause the chemical solution to be discharged from the chemicalsolution nozzle 309 toward the central portion of the upper surface ofthe substrate W while making the substrate W rotate by the spin chuck302. The chemical solution is thereby supplied to the entire uppersurface of the substrate W and the substrate W is processed by thechemical solution (chemical solution processing). Then, when thechemical solution processing has been performed for a predeterminedtime, the controller 327 closes the chemical solution valve 311 to stopthe discharge of the chemical solution. Thereafter, the controller 327makes the chemical solution nozzle 309 move to the retreat position.

Thereafter, a water rinsing processing (rinsing liquid supply step) ofsupplying pure water, which is an example of a rinsing liquid, to thesubstrate W is performed (S302). Specifically, the controller 327controls the shielding plate elevating mechanism 308 to move theshielding plate 303 from the retreat position to the processing positionwith the chemical solution nozzle 309 being positioned at the retreatposition. The controller 327 then opens the rinsing liquid valve 325 tocause pure water to be discharged from the central axis nozzle 316toward the central portion of the upper surface of the substrate W whilemaking the substrate W rotate by the spin chuck 302. The chemicalsolution held by the substrate W is thereby replaced by the pure water,and the pure water is supplied to the entire upper surface of thesubstrate W. The chemical solution adhering to the substrate W isthereby rinsed off by the pure water (water rinsing processing). Then,when the water rinsing processing has been performed for a predeterminedtime, the controller 327 closes the rinsing liquid valve 325 to stop thedischarge of pure water.

Thereafter, a first solvent rinsing processing (water-soluble solventsupply step) of supplying IPA, which is an example of a water-solublesolvent, to the substrate W is performed (S303). Specifically, thecontroller 327 opens the water-soluble solvent valve 321 to cause IPA tobe discharged from the central axis nozzle 316 toward the centralportion of the upper surface of the substrate W while positioning theshielding plate 303 at the processing position and further making thesubstrate W rotate by the spin chuck 302. The IPA discharged from thecentral axis nozzle 316 is thereby supplied to the entire upper surfaceof the substrate W. A large portion of the pure water held by thesubstrate W is rinsed off by the IPA. Also, IPA is capable of dissolvingwater, and thus a portion of the pure water held by the substrate Wdissolves into the IPA and is removed (discharged) from the substrate Wtogether with the IPA. The pure water is thus removed from the substrateW and the pure water held by the substrate W is replaced by the IPA(first solvent rinsing processing). Then, when the first solvent rinsingprocessing has been performed for a predetermined time, the controller327 closes the water-soluble solvent valve 319 to stop the discharge ofIPA. By performing the first solvent rinsing processing, water isremoved from the substrate W and a residual amount of water on thesubstrate W is reduced.

Thereafter, a second solvent rinsing processing (first solvent supplystep, replacement step) of supplying PGMEA, which is an example of thefirst solvent, to the substrate W is performed (S304). Specifically, thecontroller 327 opens the second solvent valve 319 to cause PGMEA to bedischarged from the central axis nozzle 316 toward the central portionof the upper surface of the substrate W while positioning the shieldingplate 303 at the processing position and further making the substrate Wrotate by the spin chuck 302. The PGMEA discharged from the central axisnozzle 316 is thereby supplied to the entire upper surface of thesubstrate W. As mentioned above, the first solvent is capable ofdissolving the water-soluble solvent and thus the IPA held by thesubstrate W dissolves into the PGMEA supplied to the substrate W and isremoved (discharged) from the substrate W together with the PGMEA. Thus,by supplying PGMEA, the IPA held by the substrate W is rinsed off by thePGMEA and replaced by the PGMEA (second solvent rinsing processing).Then, when the second solvent rinsing processing has been performed fora predetermined time, the controller 327 closes the second solvent valve319 to stop the discharge of PGMEA. Even if pure water remains on thesubstrate W or pure water is dissolved in the IPA held by the substrateW after the first solvent rinsing processing has been performed, theresidual amount of water on the substrate W is further reduced byperforming the second solvent rinsing processing.

Thereafter, a third solvent rinsing processing (first solvent supplystep, physical replacement step) of applying vibration to PGMEA, whichis an example of the first solvent, and supplying the vibration-appliedPGMEA to the substrate W is performed (S305). Specifically, thecontroller 327 controls the shielding plate elevating mechanism 308 tomove the shielding plate 303 from the processing position to the retreatposition. Thereafter, the controller 327 moves the solvent nozzle 312from the retreat position to the processing position. The controller 327then opens the first solvent valve 314 to cause PGMEA to be dischargedfrom the solvent nozzle 312 toward the central portion of the uppersurface of the substrate W while making the substrate W rotate by thespin chuck 302. The PGMEA, to which vibration is applied by theultrasonic transducer 315, is thereby supplied to the entire uppersurface of the substrate W and the PGMEA held by the substrate W isreplaced by the PGMEA discharged from the solvent nozzle 312 (thirdsolvent rinsing processing). Vibration is applied to the PGMEA suppliedto the substrate W and thus even if pure water is left on the substrateW (for example, at bottom portions of the cylinders S; see FIG. 26), thepure water is stirred by the vibration of the PGMEA and is removed fromthe substrate W together with the PGMEA. The pure water is therebyremoved from the substrate W. Then, when the third solvent rinsingprocessing has been performed for a predetermined time, the controller327 closes the first solvent valve 314 to stop the discharge of PGMEA.The residual amount of water on the substrate W is thus further reducedby performing the third solvent rinsing processing.

Thereafter, a hydrophobization processing (hydrophobizing agent supplystep) of supplying the hydrophobizing agent (liquid) to the substrate Wto hydrophobize the substrate W is performed (S306). Specifically, thecontroller 327 moves the solvent nozzle 312 from the processing positionto the retreat position. Thereafter, the controller 327 controls theshielding plate elevating mechanism 308 to move the shielding plate 303from the retreat position to the processing position. The controller 327then controls the hydrophobizing agent supply unit 318 to cause thehydrophobizing agent to be discharged from the central axis nozzle 316toward the central portion of the upper surface of the substrate W whilepositioning the shielding plate 303 at the processing position andfurther making the substrate W rotate by the spin chuck 302. Thehydrophobizing agent is thereby supplied to the entire upper surface ofthe substrate W. The hydrophobizing agent is capable of dissolving thefirst solvent, and thus by supplying the hydrophobizing agent to theentire upper surface of the substrate W, the PGMEA held by the substrateW is replaced by the hydrophobizing agent. The hydrophobizing agent isthereby made to enter into internal portions of the patterns P and theupper surface of the substrate W is hydrophobized (hydrophobizationprocessing). Then, when the hydrophobization processing has beenperformed for a predetermined time, the controller 327 controls thehydrophobizing agent supply unit 318 to stop the discharge of thehydrophobizing agent.

Thereafter, a fourth solvent rinsing processing (non-contact statemaintaining step, drying agent supply step) of supplying IPA, which isan example of the drying agent, to the substrate W is performed (S307).Specifically, the controller 327 opens the drying agent valve 323 tocause the solvent to be discharged from the central axis nozzle 316toward the central portion of the upper surface of the substrate W whilepositioning the shielding plate 303 at the processing position andfurther making the substrate W rotate by the spin chuck 302. The IPAdischarged from the central axis nozzle 316 is thereby supplied to theentire upper surface of the substrate W. A large portion of thehydrophobizing agent held by the substrate W is thus rinsed off by theIPA. Also, IPA is capable of dissolving the hydrophobizing agent, andthus the hydrophobizing agent remaining on the substrate W dissolvesinto the IPA and is removed (discharged) from the substrate W togetherwith the IPA. The hydrophobizing agent is thereby removed from thesubstrate W and the hydrophobizing agent held by the substrate W isreplaced by the IPA (fourth solvent rinsing processing). Then, when thefourth solvent rinsing processing has been performed for a predeterminedtime, the controller 327 closes the drying agent valve 323 to stop thedischarge of IPA.

Thereafter, a drying processing (drying step) of drying the substrate Wis performed (S308). Specifically, the controller 327 controls the spinmotor 306 to rotate the substrate W at a high rotation speed (forexample, several thousand rpm) with the shielding plate 303 beingpositioned at the processing position. A large centrifugal force thusacts on the IPA adhering to the substrate W and the IPA is shaken off tothe periphery of the substrate W. The IPA is thereby removed from thesubstrate W and the substrate W is dried (drying processing). After thedrying processing has been performed for a predetermined time, thecontroller 327 controls the spin motor 306 to stop the rotation of thesubstrate W by the spin chuck 302. Further, the controller 327 controlsthe shielding plate elevating mechanism 308 to move the shielding plate303 from the processing position to the retreat position. Thereafter,the substrate W that has been processed is carried out from the spinchuck 302 by the transfer robot.

FIG. 26 is a schematic sectional view of a substrate W for describing aforce applied to the patterns P.

When the substrate W with the patterns P formed thereon is dried, aforce that draws the patterns P toward each other is applied as thesubstrate W dries and the patterns P may thereby collapse. The force Fapplied to the patterns P is expressed, for example, by the followingformula (1).F=(2×σ×H cos θ)/L  (Formula 1)

“σ” is the surface tension of the processing liquid, “θ” is the contactangle, “H” is the height of the patterns P, and “L” is the intervalbetween the patterns P.

From the formula (1), it can be understood that the lower the surfacetension σ of the processing liquid, the less the force F applied to thepatterns P. Thus, by lowering the surface tension σ of the processingliquid, the force F applied to the patterns P can be decreased tothereby suppress collapse of the patterns P.

It can also be understood from the formula (1) that the force F appliedto the patterns P decreases the closer the contact angle θ is to 90degrees. Thus, by hydrophobizing the surface of the substrate W andthereby making the contact angle θ approach 90 degrees, collapse of thepatterns P can be suppressed or prevented.

That is, the collapse of the patterns P can be suppressed by loweringthe surface tension σ of the processing liquid held by the substrate Wbefore the substrate W is dried and further by making the contact angleθ approach 90 degrees. It is thus preferable to sufficientlyhydrophobize the entire surface of the substrate W to sufficientlysuppress the collapse of the patterns P.

FIG. 27 is a graph of contact angles of a processing liquid with respectto a substrate W, hydrophobized by a hydrophobizing agent, before andafter pure water is supplied to the substrate W. FIG. 28 is a graph ofcollapse rates of patterns P when a substrate W, hydrophobized by ahydrophobizing agent, is dried after supplying pure water or IPA to thesubstrate W. The collapse rate of a comparative example shown in FIG. 28is the value in a case of use of pure water in place of the drying agentin the fourth solvent rinsing processing in the processing example ofFIG. 25. On the other hand, the collapse rate of an example shown inFIG. 28 is the value in the case of use of IPA, which is an example of adrying agent, in the fourth solvent rinsing processing in the processingexample of FIG. 25.

As can be understood from a comparison of the two contact angles shownin FIG. 27, when pure water is supplied to the substrate W that has beenhydrophobized by the hydrophobizing agent (metal hydrophobizing agent),the contact angle of the processing liquid with respect to the substrateW decreases. As mentioned above, the force applied to the patterns Pincreases as the contact angle θ approaches 0 degrees. Thus, as shown inFIG. 28, in the case of supplying pure water to the substrate W that hasbeen hydrophobized by the hydrophobizing agent and thereafter drying thesubstrate W (comparative example), the collapse rate of the patterns Pis extremely large in comparison to the case of supplying IPA, which isan example of a drying agent (example). In other words, by supplying thedrying agent to the substrate W that has been hydrophobized by thehydrophobizing agent and thereafter drying the substrate W, the collapserate of the patterns P can be reduced significantly in comparison to thecase of supplying pure water. Further, IPA is lower in surface tensionthan water and thus in comparison to the case of drying the substrate Wthat holds pure water, the collapse rate of the patterns P is reducedsignificantly.

FIG. 29 is a graph of the collapse rate of patterns P when a substrate Wis processed by a conventional substrate processing method and thecollapse rate of patterns P when a substrate W is processed by theprocessing example of FIG. 25. That is, the collapse rate of acomparative example shown in FIG. 29 is the value in a case of drying asubstrate W after successively supplying a chemical solution, purewater, and IPA to the substrate W. On the other hand, the collapse rateof an example shown in FIG. 29 is the value obtained upon performing theseries of processing of FIG. 25. As shown by the comparative example inFIG. 29, with the conventional substrate processing method, the collapserate is high (approximately 60%) because the substrate W is nothydrophobized and the force applied to the patterns P is large. On theother hand, in the case where the substrate W is hydrophobizedsufficiently as in the example in FIG. 29, the collapse rate is low(approximately 5%) because the force applied to the patterns P is small.Thus, by performing the series of processing of FIG. 25, the collapserate of the patterns P can be reduced significantly in comparison to theconventional substrate processing method.

As described above, with the third embodiment, after the rinsing liquidthat contains water has been supplied to the substrate W, thewater-soluble solvent and the first solvent are successively supplied inthat order to the substrate W. Thereafter, the first solvent withvibration applied thereto is supplied to the substrate W. By supplyingthe water-soluble solvent, the rinsing liquid held by the substrate W isremoved from the substrate W as it dissolves into the water-solublesolvent. Also, the first solvent is supplied after the water-solublesolvent has been supplied, and thus even if the rinsing liquid remainson the substrate W, the rinsing liquid is removed from the substrate Wtogether with the water-soluble solvent in the process of replacement ofthe water-soluble solvent by the first solvent. Further, the firstsolvent with vibration applied thereto is supplied after the firstsolvent has been supplied first, and thus even if the rinsing liquidremains on the substrate W, the rinsing liquid is removed from thesubstrate W by the vibration of the first solvent in addition to theforce of flow of the first solvent along the substrate W. In a casewhere a recess portion having a bottomed cylindrical shape is formed onthe substrate W, the rinsing liquid readily remains on the substrate(especially at a bottom of the recess portion). However, by supplyingthe water-soluble solvent and the first solvent to the substrate W asdescribed above, the rinsing liquid can be removed even from the bottomof the recess portion. The residual amount of water on the substrate Wcan thus be reduced extremely.

The hydrophobizing agent is supplied to the substrate W after supplyingthe water-soluble solvent and the first solvent to the substrate W. Thehydrophobizing agent is thus supplied to the substrate W in a statewhere the rinsing liquid is not left on the substrate W or in a state inwhich the residual amount of water is extremely low. Lowering of theability of the hydrophobizing agent (the ability to hydrophobize thesubstrate W) due to contact with water can thus be suppressed orprevented. Further, the hydrophobizing agent is supplied to thesubstrate W holding the first solvent that does not contain a hydroxylgroup, and the lowering of the ability of the hydrophobizing agent dueto contact with the first solvent can thus be suppressed or prevented.Yet further, the second solvent that does not contain a hydroxyl groupis contained in the hydrophobizing agent and thus the hydrophobizingagent can be stabilized and the lowering of the ability of thehydrophobizing agent can be suppressed or prevented. The substrate W canthus be hydrophobized sufficiently by supplying the hydrophobizing agentto the substrate W. That is, the contact angle of the processing liquidwith respect to the substrate W can be made to approach 90 degrees tosuppress the collapse of the patterns P. Moreover with the processingexample described above, the second solvent contained in thehydrophobizing agent is a solvent of the same type as the first solventand the compatibility of the two is high. The first solvent held by thesubstrate W is thus replaced smoothly by the hydrophobizing agent. Timerequired for replacement from the first solvent to the hydrophobizingagent can thus be shortened.

Also, in the third embodiment, the drying agent is supplied to thesubstrate W after the hydrophobizing agent has been supplied to thesubstrate W. Thereafter, the drying agent is removed from the substrateW and the substrate W dries. Contact of the substrate W with water isprevented from the end of supply of the hydrophobizing agent to the endof drying of the substrate W. That is, a liquid or vapor containingwater is not supplied to the substrate W from the end of supply of thehydrophobizing agent to the end of drying of the substrate W. Thecontact angle of the processing liquid with respect to the substrate W,to which the hydrophobizing agent has been supplied, can thus besuppressed or prevented from decreasing due to the contact of thesubstrate W with water. Increase in the force that collapses thepatterns P when the substrate W is dried can thereby be suppressed orprevented. The collapse of the patterns P can thus be suppressed orprevented. Further, the drying agent is lower in surface tension thanwater and thus the collapse of the patterns P can be further suppressedor prevented. Moreover, the drying agent is lower in boiling point thanwater and thus time required for drying the substrate W can beshortened.

Also, in the third embodiment, the second solvent and the hydrophobizingagent stock solution are mixed inside the collective pipe 338. That is,the second solvent and the hydrophobizing agent stock solution are mixedimmediately before being supplied to the substrate W. The mixed solution(hydrophobizing agent) of the second solvent and the hydrophobizingagent stock solution that are mixed is supplied to the substrate W. Thesecond solvent and the hydrophobizing agent stock solution are mixedimmediately before being supplied to the substrate W and thus even in acase where the activity of the hydrophobizing agent decreases with theelapse of time due to dilution of the hydrophobizing agent, thehydrophobizing agent that is not decreased in activity or is hardlydecreased in activity can be supplied to the substrate W. The substrateW can thus be hydrophobized sufficiently. The collapse of the patterns Pcan thus be suppressed or prevented.

[Other Embodiments]

Although the embodiments of the present invention have been describedabove, the present invention is not restricted to the contents of theabove-described embodiments and various modifications are possiblewithin the scope of the claims.

For example, with the first processing example and the second processingexample, the case where the solvent is supplied to the substrate W inthe pre-drying rinsing processing was described. However, pure water maybe supplied to the substrate W in the pre-drying rinsing processinginstead.

Specifically, in a case where both the first hydrophobizing agent andthe second hydrophobizing agent are hydrophobizing agents besides anamine having a hydrophobic group that is an example of a metalhydrophobizing agent, the hydrophobicity of the substrate W does notdecrease significantly even when pure water is supplied to thehydrophobized substrate W and thus pure water may be supplied to thesubstrate W in the pre-drying rinsing processing. On the other hand, ina case where either the first hydrophobizing agent or the secondhydrophobizing agent is an amine having a hydrophobic group, it ispreferable to supply a solvent in the pre-drying rinsing processingbecause the hydrophobicity of the substrate W decreases significantlywhen pure water is supplied to the substrate W in the pre-drying rinsingprocessing.

Also, with each of the first processing example to the fourth processingexample, the case where a solvent is supplied to the substrate W in thefirst solvent rinsing processing, the second solvent rinsing processing,and the pre-drying rinsing processing was described. However, a vapor ofthe solvent may be supplied to the substrate W instead as long as thevapor dissolves sufficiently in the liquid adhering to the substrate W.

Also, with each of the first processing example to the fourth processingexample, the case where the first hydrophobization processing ofsupplying the first hydrophobizing agent to the substrate W is performedafter performing the first solvent rinsing processing of supplying thesolvent to the substrate W was described. However, in a case where purewater dissolves in the first hydrophobizing agent and the firsthydrophobizing agent does not decrease in activity even upon contactwith pure water, the first hydrophobization processing may be performedwithout performing the first solvent rinsing processing after performingthe water rinsing processing of supplying pure water to the substrate W.

Also, with the second processing example, the case where the secondsolvent rinsing processing of supplying the solvent to the substrate Wis performed after performing the first hydrophobization processing andbefore performing the second hydrophobization processing was described.However, in the case where the first hydrophobizing agent and the secondhydrophobizing agent readily mix together, the second hydrophobizationprocessing of supplying the second hydrophobizing agent to the substrateW may be performed without performing the second solvent rinsingprocessing after performing the first hydrophobization processing ofsupplying the first hydrophobizing agent to the substrate W.

Also, with each of the first processing example to the fourth processingexample, the case where a liquid or a vapor of the hydrophobizing agentthat has been diluted to a fixed concentration is supplied to thesubstrate W in the first hydrophobization processing and the secondhydrophobization processing was described. However, the concentration ofthe hydrophobizing agent may be increased in a continuous or stepwisemanner by the controller 22 controlling the opening degrees of the flowregulating valves 28 and 30 (see FIG. 4 and FIG. 18). In this case, thesolvent adhering to the substrate W can be replaced smoothly by thehydrophobizing agent in the first hydrophobization processing and thesecond hydrophobization processing, and thus time required to remove thesolvent from the substrate W can be shortened.

Also, with each of the first processing example to the fourth processingexample, the case of processing the substrate W by causing theprocessing liquids to be discharged from the chemical solution nozzle 10and the central axis nozzle 14 were described. However, the substrate Wmay instead be processed by making a liquid film of the processingliquid be held on the substrate W. Specifically, a processing liquid isdischarged from the chemical solution nozzle 10 or the central axisnozzle 14 while making the substrate W rotate at a low rotation speed ofabout 10 to 30 rpm by the spin chuck 2 or while stopping the rotation ofthe substrate W. Then, after a liquid film of the processing liquid thatcovers the upper surface of the substrate W is formed, the discharge ofthe processing liquid is stopped. Thereafter, in the state where thedischarge of the processing liquid is stopped, the substrate W isprocessed by the liquid film of the processing liquid while making thesubstrate W rotate at the low rotation speed or while stopping therotation of the substrate W.

Also, with each of the first processing example to the fourth processingexample, the case where pure water, which is an example of the rinsingliquid, is supplied to the substrate in the water rinsing processing wasdescribed. However, the rinsing liquid is not restricted to pure waterand a rinsing liquid besides pure water may be supplied to the substrateinstead.

Also, with each of the first processing example to the fourth processingexample, the case of processing substrate W with the patterns P of thelaminated film 32 formed thereon was described. However, a substrate Whaving patterns P of a single film may also be processed. For example, asubstrate W, having patterns P of only an SiN film formed thereon, canbe processed as described above using a silicon hydrophobizing agentwith a long hydrophobic group or a silicon hydrophobizing agent with ashort hydrophobic group in accordance with the second processing exampleor the fourth processing example to hydrophobize the SiN filmsufficiently.

Also, although in each of the second processing example and the fourthprocessing example, the hydrophobization processing is performed twiceusing the first hydrophobizing agent and the second hydrophobizingagent, the hydrophobization processing may be performed further for athird time using a third hydrophobizing agent. For example, in the caseof the film combination shown in FIG. 10, a hydrophobization processingof the metal film may be preformed using a metal hydrophobizing agent asthe first hydrophobizing agent, a hydrophobization processing of the SiNfilm may be performed using the silicon hydrophobizing agent I with thelong hydrophobic group as the second hydrophobizing agent, and furtherhydrophobization processing of the SiN film may be performed using thesilicon hydrophobizing agent II with the short hydrophobic group as thethird hydrophobizing agent.

Also, with each of the first processing example to the fourth processingexample, the case of processing the substrate W one at a time wasdescribed. However, in each of the first processing example to thefourth processing example, a plurality of substrates W may be processedin a batch.

Also, with the third embodiment, the case where the first solventrinsing processing (water-soluble solvent supply step), the secondsolvent rinsing processing (replacement step), and the third solventrinsing processing (physical replacement step) are performedsuccessively after performing the water rinsing processing (rinsingliquid supply step) and before performing the hydrophobizationprocessing (hydrophobizing agent supply step) was described. However,the first solvent rinsing processing and one of the second solventrinsing processing and the third solvent rinsing processing may beomitted. Or one of the second solvent rinsing processing and the thirdsolvent rinsing processing may be omitted.

Also, with the third embodiment, the case where the liquids of the firstsolvent, the hydrophobizing agent, the water-soluble solvent, and thedrying agent are supplied to the substrate W was described. However, avapor of the first solvent may be supplied to the substrate W instead.The same applies to the hydrophobizing agent, the water-soluble solvent,and the drying agent. The vapor may be that obtained by gasification ofa compound (for example, the first solvent) to be supplied, or may be amixed fluid containing liquid droplets of the compound to be suppliedand a carrier gas (for example, nitrogen gas or other inert gas) thatcarries the liquid droplets.

Also, with the third embodiment, the case where a processing liquid isdischarged from one of the nozzles throughout the processing of thesubstrate W by the processing liquid was described. However, thesubstrate W may instead be processed by making a liquid film of theprocessing liquid be held on the substrate W. That is, a puddleprocessing may be performed in which the liquid film of the processingliquid is held on the substrate to make the processing progress whilestopping the supply of the processing liquid to the substrate W.

Specifically, a processing liquid is discharged from one of the nozzleswhile making the substrate W rotate at a low rotation speed of about 10to 30 rpm by the spin chuck 302 or while stopping the rotation of thesubstrate W. The discharge of the processing liquid is then stoppedafter the liquid film of the processing liquid that covers the uppersurface of the substrate W is formed. Thereafter, the substrate W isrotated at the low rotation speed or the rotation of the substrate W isstopped in the state where the discharge of the processing liquid isstopped. The substrate W is thereby processed in the state where theliquid film of the processing liquid is held on the substrate W.

Also, with the third embodiment, the case where the hydrophobizationprocessing (hydrophobizing agent supply step), the fourth solventrinsing processing (drying agent supply step), and the drying processing(drying step) are performed successively was described. However, thehydrophobizing agent may be supplied to the substrate W again afterperforming the hydrophobization processing and before performing thefourth solvent rinsing processing. That is, the hydrophobizationprocessing may be performed a plurality of times. In this case, thehydrophobizing agent used in the hydrophobization processing (firsthydrophobizing agent supply step) that is performed first and thehydrophobizing agent (second hydrophobizing agent) used in thehydrophobization processing (second hydrophobizing agent supply step)performed next may be metal hydrophobizing agents of the same type ormay be metal hydrophobizing agents (second hydrophobizing agents) ofdifferent types. Also, one of the first hydrophobizing agent and thesecond hydrophobizing agent may be a metal hydrophobizing agent and theother may be a silicon hydrophobizing agent.

A silicon hydrophobizing agent is a hydrophobizing agent thathydrophobizes silicon (Si) itself or a compound that contains silicon.The silicon hydrophobizing agent is, for example, a silane couplingagent. The silane coupling agent contains, for example, at least one ofHMDS (hexamethyldisilazane), TMS (tetramethylsilane), a fluorinatedalkylchlorosilane, an alkyldisilazane, and a nonchloro hydrophobizingagent. The nonchloro hydrophobizing agent contains, for example, atleast one of dimethylsilyldimethylamine, dimethylsilyldiethylamine,hexamethyldisilazane, tetramethyldisilazane, bis(dimethylamino)dimethylsilane, N,N-dimethylaminotrimethylsilane,N-(trimethylsilyl)dimethylamine, and an organosilane compound.

Also, with the third embodiment, the case where the first solvent, towhich vibration is applied, is discharged from the solvent nozzle 312 asan ultrasonic nozzle was described. However, a liquid droplet formingnozzle 439 (liquid droplet forming unit) shown in FIG. 30 may beprovided in place of the ultrasonic nozzle. The liquid droplet formingnozzle 439 is a nozzle that forms liquid droplets of the first solventthat are blown onto the substrate W held by the spin chuck 302. Thus, bycausing the first solvent to be discharged from the liquid dropletforming nozzle 439, the liquid droplets of the first solvent collidewith the substrate W (step of making liquid droplets of the firstsolvent collide with the substrate), and the rinsing liquid held by thesubstrate is removed by kinetic energy of the liquid droplets. Theliquid droplet forming nozzle 439 may be a two-fluid nozzle that formsliquid droplets of the first solvent by making the liquid of the firstsolvent collide with a gas, or an inkjet nozzle that jets liquiddroplets of the first solvent by application of vibration to the firstsolvent by a piezoelectric element. In a case where the liquid dropletforming nozzle 439 is provided in place of the ultrasonic nozzle, theultrasonic transducer 315 may be mounted to the liquid droplet formingnozzle 439 and vibration may be applied to the liquid droplets of thefirst solvent that are jetted toward the substrate W.

Also, with the third embodiment, the case where the hydrophobizing agentthat has been diluted to a fixed concentration by the second solvent issupplied to the substrate W was described. However, an undilutedhydrophobizing agent (hydrophobizing agent stock solution) may besupplied to the substrate W instead. Or, when the hydrophobizing agentis being supplied to the substrate W, the controller 327 may control theopening degrees of the first flow regulating valve 334 and/or the secondflow regulating valve 337 to increase the concentration of thehydrophobizing agent in a continuous or a stepwise manner.

Also, with the third embodiment, the case where the hydrophobizing agentstock solution and the second solvent are mixed in the collective pipe338 was described. However, the mixing of the hydrophobizing agent stocksolution and the second solvent is not restricted to the collective pipe338 and may be performed at any position of the flow path of thehydrophobizing agent leading from the hydrophobizing agent tank 328 tothe substrate W held by the spin chuck 302. Specifically, thehydrophobizing agent stock solution and the second solvent may be mixedat any of the first pipe 330, the processing liquid supply pipe 317, andthe central axis nozzle 316. Further, the hydrophobizing agent stocksolution and the second solvent may be mixed in between the central axisnozzle 316 and the substrate W or may be mixed on the substrate W.

Also, with the third embodiment, the case of drying the substrate W byremoving the liquid from the substrate W by making the substrate Wrotate at a high rotation speed by the driving force of the spin motor306 was described. However, a gas nozzle that blows a gas, such asnitrogen gas or other inert gas or clean air, etc., onto the substrate Wmay be provided and the substrate W may be dried by removal of theliquid from the substrate W by the gas discharged from the gas nozzle.

Also, with the third embodiment, the case where the hydrophobizingagent, the water-soluble solvent, the drying agent, and the rinsingliquid are discharged from a nozzle in common (central axis nozzle 316)was described. However, the hydrophobizing agent, the water-solublesolvent, the drying agent, and the rinsing liquid may be dischargedrespectively from dedicated nozzles instead.

While the embodiments of the present invention have been described indetail above, these are merely specific examples used for clarifying thetechnical contents of the present invention, and the present inventionshould not be interpreted as being restricted to these specificexamples, and the spirit and scope of the present invention are limitedsolely by the appended claims.

The present application corresponds to Japanese Patent Application No.2010-185415 filed in the Japan Patent Office on Aug. 20, 2010, JapanesePatent Application No. 2011-071590 filed in the Japan Patent Office onMar. 29, 2011, and Japanese Patent Application No. 2011-099529 filed inthe Japan Patent Office on Apr. 27, 2011, and the entire disclosures ofthe applications are incorporated herein by reference.

What is claimed is:
 1. A substrate processing method comprising: ahydrophobizing step of supplying a liquid of a hydrophobizing agent to asubstrate to hydrophobize a surface of the substrate; a drying step ofdrying the substrate after performing the hydrophobizing step; a step ofmaintaining the substrate in a state of not contacting water from theend of the hydrophobizing step to the end of the drying step; and apre-drying rinsing step of supplying a solvent, lower in surface tensionthan water and capable of dissolving the hydrophobizing agent, to thesubstrate after performing the hydrophobizing step and before performingthe drying step.
 2. The substrate processing method according to claim1, wherein the substrate is a substrate that includes a metal film.
 3. Asubstrate processing method for processing a substrate having a metalfilm formed thereon, the substrate processing method comprising: arinsing liquid supply step of supplying a rinsing liquid that containswater to the substrate; a first solvent supply step of supplying a firstsolvent that does not contain a hydroxyl group to the substrate toreplace a liquid held by the substrate by the first solvent afterperforming the rinsing liquid supply step; and a hydrophobizing agentsupply step of supplying a hydrophobizing agent, which contains a secondsolvent that does not contain a hydroxyl group and which hydrophobizes ametal, to the substrate to replace a liquid held by the substrate by thehydrophobizing agent after performing the first solvent supply step;wherein the first solvent supply step includes a physical replacementstep of supplying the substrate with the first solvent with a physicalforce to replace a liquid held by the substrate by the first solvent. 4.The substrate processing method according to claim 3, wherein the firstsolvent supply step further includes a replacement step of supplying thefirst solvent to the substrate to replace a liquid held by the substrateby the first solvent before the physical replacement step is performed.5. The substrate processing method according to claim 3, wherein thephysical replacement step includes at least one of either a step ofsupplying the first solvent with vibration to the substrate or a step ofmaking liquid droplets of the first solvent provided with kinetic energycollide with the substrate.
 6. A substrate processing method forprocessing a substrate on which a pattern of a laminated film having alower layer film and an upper layer film is formed, the substrateprocessing method comprising: a first hydrophobizing step of supplying afirst hydrophobizing agent to a substrate to hydrophobize a surface ofthe substrate; a second hydrophobizing step of supplying a secondhydrophobizing agent that differs from the first hydrophobizing agent tothe substrate to hydrophobize the surface of the substrate afterperforming the first hydrophobizing step; and a drying step of dryingthe substrate after performing the second hydrophobizing step; whereinthe first hydrophobizing agent is a hydrophobizing agent thathydrophobizes the lower layer film, and the second hydrophobizing agentis a hydrophobizing agent that hydrophobizes the upper layer film.